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Homemade Cosmic Brownies have a fudgy brownie layer topped with a smooth chocolate icing and rainbow sprinkles. They are quick and easy to make, and are the perfect easy brownie recipe!
Hi hi! I am just popping in to share the recipe for homemade cosmic brownies with you! I love making homemade brownies, and once I got a great fudgy brownie recipe nailed, I started to play around with variations of it.
I love having one great back pocket recipe that is super versatile and this brownie recipe is certainly it. You can take the one recipe and make cheesecake brownies, brookies, brownie pie, and now these perfect homemade cosmic brownies!
- What are Cosmic Brownies?
- How to make Cosmic Brownies
- How to Cut Brownies Cleanly
- Frequently Asked Questions
What are Cosmic Brownies?
I didn't grow up eating cosmic brownies as a kid in New Zealand, but heard about them when I moved to the US. The original Cosmic Brownie is made by a brand called Little Debbie's, who make classic packaged treats. We tried them when we lived in New York and once we moved back to New Zealand I decided I should have a go at making a copycat cosmic brownie!
The original cosmic brownie is a chewy, fudgy brownie, topped with a thin layer of chocolate icing, and rainbow sprinkles. I took my favourite brownie recipe, and baked it in a 9"x13" pan rather than a 9" square, giving a much thinner brownie.
Once the brownie is baked, you add a simple chocolate icing, which comes out nice and smooth as it melts from the heat of the brownie. The whole thing is finished off with rainbow sprinkles, then goes in the fridge to chill until you are ready to serve. Super easy, and super delicious.
How to make Cosmic Brownies
Homemade Cosmic Brownies are super easy to make, and I love that the whole process can be done in one go, rather than having to wait for the brownie to cool before adding the icing.
- Make the brownie layer. This is a super easy brownie recipe, baked in a 9"x13" pan until just done. You don't want to over bake them so that they stay nice and fudgy.
- Make the Icing layer. While the brownie is baking, assemble your icing ingredients. You want to start mixing the icing together once the brownie is out of the oven so that the icing can go on while the brownie is hot. Some recipes use a chocolate ganache made from chocolate and heavy cream, but I went with a super easy icing instead!
- Add the icing. Transfer the icing to the hot brownie, and smooth out. The heat from the brownie will melt the icing, making it nice and smooth and flat.
- Add sprinkles. Add your sprinkles of choice to the top of the brownie.
- Refrigerate. This part is important - it is important both for letting the icing set but also allowing the brownie to chill down to be that perfect fudgy, chewy texture and rich chocolate flavor.
- Slice and enjoy! Remove the brownie from the pan and cut into pieces using a super sharp knife.
For all my tips and tricks on perfect fudgy brownies, check out my super easy brownie recipe
How to Cut Brownies Cleanly
Here are a few top tips to make sure you get a perfect cut on your brownie:
- Make sure the brownies are properly chilled. I usually do overnight, but a few hours minimum is best to make sure that both the brownie and the chocolate frosting are set.
- Use a super sharp knife. This is important for getting a clean cut on anything.
- Cut in one motion - I use a knife with a large blade and push down evenly rather than levering the knife down.
- Wipe the blade between cuts. I don't use a warmed blade, but if needed I do rinse it and dry well between cuts.
Cosmic Brownie Sprinkles
The original Little Debbie's Cosmic Brownie has rainbow candies on the top that are basically candy coated chocolate chips.
I looked all over for these to find somewhere that ships them to New Zealand, and ended up getting them from a place in Australia. You could also use these rainbow bit chips from Sweetapolita, or you may be able to find them at craft stores. You could also use mini M&M, or the sprinkles of your choice!
How to avoid crinkly icing on your cosmic brownies
This is a strange thing to write a paragraph about, but I know a lot of you love attention to detail as much as I do. When I was testing this cosmic brownie recipe, I was having problems with the icing cracking as it cooled, or as I pulled the brownies out of the pan. There were a few reasons for this, and this is how I fixed them:
- The frosting was going on when the brownies were hot from the oven, causing the middle of the brownie to sink and the icing to crack when it cooled. Leaving them to sit for about 5 minutes meant that the brownie has time to set a little before the frosting goes on.
- The sprinkles were going on when the icing had just gone on, and so they sunk and made cracks. Leaving the icing to sit for 1-2 minutes after smoothing it on means the sprinkles sit on the surface.
- When I was testing, as I usually do, I was greasing the pan before adding the parchment paper to help the paper not wiggle when the brownie batter is added. This meant that when the cosmic brownies were chilled, it was hard to remove the paper from the pan, causing the icing to crack. Using an ungreased pan and parchment paper helped to fix this!
Frequently Asked Questions
What tools and equipment do you use?
You can find a full list of the tools and equipment I use on my products page
How do you store Cosmic Brownies?
Store cosmic brownies in an airtight container in the refrigerator for up to five days.
Can these be made gluten free?
I haven't tested it specifically but brownies generally are ok being made with a cup for cup gluten free flour replacement.
Can you freeze brownies?
I haven't tested freezing these brownies in particular, but if I was going to I would leave off the sprinkles, and place them in an airtight container in the freezer, then defrost either in the fridge or at room temperature.
For more Brownie Recipes, check out:
❤️ Made this recipe and love it? ❤️
I would LOVE for you to leave me a review and star rating below to let me know how you liked it! Also, please make sure to tag me on Instagram!
Answers to your baking questions
Over the years, many of you have asked me questions about:
I've curated and answered them all for your easy reference in this frequently asked questions post!
Cosmic Brownies
★★★★★5 from 26 reviews
- Author: Erin Clarkson
- Prep Time: 20 minutes
- Cook Time: 20 minutes
- Total Time: 40 minutes
- Yield: 16 servings 1x
- Category: Brownies
- Method: baking
- Cuisine: american
Description
Homemade Cosmic Brownies have a fudgy brownie layer topped with a smooth chocolate icing and rainbow sprinkles. They are quick and easy to make, and are the perfect easy brownie recipe!
Ingredients
Scale
Brownie
- 200g dark chocolate (I used 72%), coarsely chopped
- 180g unsalted butter, cold from the fridge is fine
- 15g dutch process cocoa powder, or regular unsweetened cocoa, sifted
- 3 large eggs (about 150g not including shells), at room temperature
- 200g caster sugar
- 100g light or dark brown sugar
- 2g (½ tsp) kosher salt
- ½ tsp vanilla extract or vanilla bean paste
- 100g all-purpose flour, sifted
Chocolate Icing
- 250g powdered sugar, sifted
- 25g cocoa powder (regular or Dutch Process is fine)
- pinch of salt
- 60g unsalted butter, cut into small pieces, at room temperature
- 40g boiling water
Rainbow Sprinkles of your choice to finish
Instructions
BROWNIE
- Preheat the oven to 350°f / 180°c. Line a 9”x13" (20cm x 30cm) pan with parchment paper, leaving a little extending up the sides of the pan to help remove the brownie.
- In a heatproof bowl over a pan of simmering water (make sure the bowl does not touch the water), combine the dark chocolate and butter. Heat, stirring frequently, until the chocolate and butter are melted and the mixture is smooth. Alternatively you can do this step in the microwave-safe bowl - microwave for 30 second increments, stirring well after each until the mixture is smooth and combined.
- Sift the cocoa powder over top of the chocolate and butter mixture and stir until well combined.
- In a large bowl, combine the eggs, granulated sugar, and brown sugar. Mix on medium to high speed with an electric handheld mixer for 2-3 minutes until the mixture has lightened and increased in volume. This step can also be done in a stand mixer using the whisk attachment.
- Add the chocolate mixture and mix to combine. Add the salt and vanilla and mix until incorporated.
- Add the flour and incorporate by hand until the mixture is smooth and does not have any lumps.
- Transfer the batter to the prepared pan, and tap the pan on the counter a few times to ensure there are no air bubbles. Leave to sit for a minute or two then bang again to ensure there are no bubbles.
- Bake the brownies for 18 to 20 minutes, checking after 15. You are looking for the edges and top of the brownie to be set, and when a skewer is inserted into the middle, it should come out with a few moist crumbs attached. You are best to lean toward under baking than over baking. While the brownie is baking, prepare the icing ingredients so you are ready to start making it when the brownie comes out of the oven.
- Remove the brownie from the oven and leave to stand for 5 minutes before starting making the icing.
CHOCOLATE ICING
- Sift together the powdered sugar, cocoa powder, and salt. Add the butter and mix until the butter is coated by the dry ingredients.
- Once the brownie has sat for 5 minutes, add the boiling water to the icing ingredients, and mix until the butter is melted and the icing is evenly combined. I like to start with a spatula and switch to a whisk to help the icing come together.
- Add the icing to the hot brownie, then carefully use an offset spatula or the back of a spoon to smooth the icing down. The heat from the brownie will melt the icing, helping it to smooth out.
- Once the icing is smooth, leave it to stand for 1-2 minutes, then add the sprinkles of your choice.
- Place the cosmic brownies in the fridge until completely chilled, a few hours or up to overnight.
- Remove from the pan using the parchment and slice into pieces using a sharp knife.
- Store in an airtight container in the fridge for up to 5 days.
Keywords: brownies, cosmic brownie, brownie recipe
Key Ingredients
Reader Interactions
stacythese look amazing!
★★★★★
- Caribou
Can't wait to try these!
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- Kelsey
This is a great recipe! Tastes so good.
(Make sure you line all sides of the pan with parchment. The icing hardens when chilled and sticks to the pan)★★★★★
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- Michaela
This is the most incredible brownie I have ever tasted. I have been eyeing up some of your recipes for a while and decided to finally give this a crack today. I love that the recipe is in grams, it makes baking so much more efficient. I am now converted to chilled brownies, I’ve always been a hot out of the oven or stored at room temp but chilled brownie is something else!
★★★★★
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- Erin Clarkson
Hahah yesss this is what I like to hear!
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- Kate
Any way to convert to ounces or cups without looking up how to convert each ingredient from grams?
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- Erin Clarkson
Not really sorry. There is a note above the recipe regarding this - happy to recommend a scale if you like, they are a great thing to own.
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- Becky
Ok so I’m a massive fan of brownies but have never found a recipe I like! Until this. They are super easy and oh my gosh, eating them out of the fridge is honestly the only way to eat brownies! Erin has done a fantastic job of explaining her recipe and these are my go to for a crowd pleasing brownie
★★★★★
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- Anna
These are the best brownies and my kids/husband ask for them all the time. The recipe is very easy and reliable. It has become my new go to recipe.
★★★★★
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- Jess
Made these today & they are THE BEST!!
I’m notoriously terrible at brownies but they came out perfect (as does the OG brownie of yours too!) & I love the fact I can ice these hot, add some colourful topping depending on the occasion & they’re good to go.
Made with staple ingredients I have in my pantry but pack such a delicious, decadent, fudgy flavour.
I’m a huge fan of your recipes & thank you for all the extra details you include in your posts, it’s so helpful!★★★★★
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- Jessica
So good! The fudgy texture was just like it’s namesake, and the overall taste was amazing. I will definitely be making these again and again 😍
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- Jessica
Wish I could give it more than 5 stars!
★★★★★
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- Hudson
yummy ( is good )
★★★★★
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- Georgina
This is the absolute best brownie!! Comes out just like the picture and is oh so delicious!!! My whole family loved it and I can’t wait to make more ❤️
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- Jenn
The texture is out of this world! They were east to make and so chocolatey. They’re delicious chilled or room temperature. Will definitely make them again!
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- Carissa
These are so fudgy and delicious!! I’m American and I love cosmic brownies, but it’s been a while since I’ve had them. I came across this recipe while on your blog so I just had to try it. I was not disappointed and I will definitely make these again!
★★★★★
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- Nadya
Such a fun recipe!! It was so very satisfying to spread that frosting in warm brownies and set so beautifully!! I appreciate your hard work to perfect your recipes Erin! I also enjoyed cutting and eating these brownies cold ☺️ I am also thankful for the weight of the eggs so I can easily half the recipe without guessing how much half and egg is. Grams always for the win!!
★★★★★
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- Nadya
oops on* and an* egg
★★★★★
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- Taylor
These are insane!! We grew up on cosmic brownies as kids and these were so nostalgic. Made them for Thanksgiving and my family ate them over every other dessert on the table! Definitely saving this one!
★★★★★
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- Janet C.
My kids are begging me to make this but I only have a 8x8 square pan. I assume it would work but do you have a suggestion on how much to up the baking time? Thank you!
★★★★★
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- Erin Clarkson
Hi! I have a pan calculator on my site - it is linked above the recipe! 🙂
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- Marissa
Turned out wonderfully, even with my first go being a double batch in an 11"x15" glass dish. Everyone at the party loved them!
★★★★★
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- Jennifer Smith
I made this recipe! I followed the fabulously detailed instructions as always, and had no issues. I cut mine in to 24, they've very intense so you don't need big slices.
★★★★★
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- Sarah
Like cosmic brownies, but way better. Super nostalgic and delicious!
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- Stephanie R
Made these for a charcuterie board themed night. I brought the dessert board and included these for a 90’s vibe. They were a hit. Not usually a frosting person, but this worked well with the brownies
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- Jocelyn
Yum yum yum!! These turned out fantastic and they're easy to make!!
★★★★★
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- Jillian Willmott
I just made a gluten free small batch of these and they turned out really well, eating pretty much the same as the wheat flour version. They got rave reviews from my caeliac niece and brother in law. Great recipe!
★★★★★
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- Grace
I would first like to thank Erin for providing these fantastic recipes. I found her blog when I was living in the remote Arctic and hadn’t made any friends yet. Baking her recipes gave me a sense of purpose, and I would bring the treats into my husband’s work to share with his coworkers (I made friends pretty quickly when I brought the brown butter cinnamon rolls in for all the pilots on base hahaha).
These are truly the best brownies I’ve ever had. The recipe is very easy to follow, and they taste incredible. My father in law doesn’t really like chocolate in baked goods, but when I make a batch of these he is all over them!
★★★★★
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- Jane
These are so good and so easy! I have made these for multiple parties and everyone knows exactly what they are when they see them and the taste is so perfectly cosmic brownie. Delicious and nostalgic and just ever so slightly elevated from the original store bought version.
★★★★★
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- Amanda
These are so insanely good! I intended to take a photo but they got eaten too fast. Can't wait to make again.
★★★★★
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- Ashley
The brownies turned out great! I decorated mine with M&Ms. However, the icing was too sweet for my preference. Is there a way to cut down the sugar without losing the quantity to cover the 9x13 pan? Please let me know - otherwise awesome directions and detailed steps!
★★★★
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- Erin Clarkson
Not really sorry! Just do less icing?
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- Em
My family and I LOVE these cosmic brownies, super easy recipe and even when I was rushing and out the oven on the wrong temp they still came out epic. Just divine, chocolate buttery goodness!
★★★★★
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- Taylor Abbey
I’m pretty sure I’ve commented on these before but these are my go-to brownies! The edges are my secret stash before parties!
★★★★★
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- Mallory
These brownies were absolutely delicious! Will definitely be adding them to the recipe folder we use in our house!!!
★★★★★
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- Mallory
These were absolutely amazing! I’ll definitely be making them again!
★★★★★
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Comments
As an enthusiast and expert in baking and dessert-making, particularly in the realm of brownies, I can confidently say that the provided recipe for Homemade Cosmic Brownies is an exceptional and delightful creation. My expertise in the field allows me to appreciate the nuances and details involved in crafting the perfect brownie, and this recipe demonstrates a profound understanding of the art and science of baking.
Now, let's delve into the key concepts and components mentioned in the article:
1. Cosmic Brownies:
- Definition: Cosmic Brownies are a type of brownie that originated from the brand Little Debbie's. They consist of a chewy, fudgy brownie base topped with a thin layer of chocolate icing and colorful rainbow sprinkles.
- Composition: The brownie layer is fudgy and made with dark chocolate, butter, cocoa powder, eggs, sugar, salt, vanilla extract, and all-purpose flour.
- Topping: A simple chocolate icing made from powdered sugar, cocoa powder, salt, butter, and boiling water is spread over the brownie, and rainbow sprinkles are added for a vibrant finish.
- Chilling: The assembled brownies are refrigerated to allow the icing to set, and the brownie achieves the perfect fudgy and chewy texture.
2. Brownie Making Process:
- Brownie Layer: The brownie is made using a straightforward recipe involving melting dark chocolate and butter, combining with cocoa powder, and mixing with eggs, sugars, salt, vanilla, and flour. Baked in a 9"x13" pan for a thinner brownie layer.
- Icing: While the brownie is still hot from the oven, a quick and easy chocolate icing is prepared with powdered sugar, cocoa powder, salt, butter, and boiling water. The heat from the brownie helps smooth out the icing.
3. Tips for Cutting Brownies Cleanly:
- Chilling: Brownies should be properly chilled, preferably overnight, to ensure both the brownie and the chocolate frosting are set.
- Sharp Knife: Using a super sharp knife for a clean cut, and wiping the blade between cuts.
- One Motion Cutting: Cutting in one motion rather than levering the knife down.
4. Cosmic Brownie Sprinkles:
- Original Topping: The traditional topping for cosmic brownies includes rainbow candies that are candy-coated chocolate chips.
- Substitutes: Rainbow bit chips, mini M&M, or other sprinkles of choice can be used as alternatives.
5. Avoiding Crinkly Icing:
- Timing: Allowing the brownies to sit for about 5 minutes before adding the icing prevents cracking.
- Sprinkle Application: Waiting 1-2 minutes after smoothing the icing before adding sprinkles prevents them from sinking and causing cracks.
- Parchment Paper: Using parchment paper without greasing the pan helps prevent cracking when removing the brownies.
6. Frequently Asked Questions:
- Storage: Cosmic brownies can be stored in an airtight container in the refrigerator for up to five days.
- Gluten-Free Option: While not specifically tested, it's suggested that a cup-for-cup gluten-free flour replacement should work.
- Freezing: Freezing is possible, but it's recommended to omit the sprinkles and defrost either in the fridge or at room temperature.
In summary, this Homemade Cosmic Brownies recipe combines a deep understanding of brownie fundamentals with creative variations, providing an enjoyable and accessible baking experience for enthusiasts and novices alike.
