When you're done frying, save your oil and reuse it up to five times. Let the oil cool completely in the pot or the deep fryer and then pour it through a paper towel–lined strainer to remove any particles. Transfer used oil to a disposable container, such as a clean milk carton or the original bottle, and store it in a dark location.
When oil has been used about five times, or has darkened, it's time to throw it out. Don't dump it down the drain though—either pour the cooled oil into a disposable container and discard, or better, look for oil recycling centers in your area.
Tools
At-home doughnut making doesn't require a countertop deep fryer, and most cooks likely already own the few tools required. In addition to the more basic kitchen items, such as a rolling pin for rolling out yeast doughnuts or a slotted spoon for removing doughnuts from the hot oil, you'll want to have the following items out and ready before you get started.
Kitchen Scale
While not essential, a kitchen scale makes it super-simple to measure flour and sugar consistently time after time. Flour, in particular, tends to compress when measured in cups, leading to excess flour being incorporated into dough. A scale also makes it very easy to double or halve a recipe. If you are a frequent baker, a kitchen scale is a must-have.
Stand Mixer with Paddle Attachment and Dough Hook
Although you can certainly make cake or raised doughnuts without one, a stand mixer with a dough hook takes the work out of kneading the dough to activate the gluten. It also reduces the likelihood of adding too much flour to the dough, which can make doughnuts tough. If a stand mixer isn't an option, cake doughnuts can be made with a hand mixer, but raised doughnuts are better worked with a wooden spoon and then kneaded by hand.
Pastry Bag and ½" Circular Tip
A pastry or piping bag fitted with a ½-inch circular tip is used to create round-bottomed cake doughnuts. You can also use a star-shaped tip to create ridged crullers. Lost your pastry bag? The cut corner of a resealable plastic bag can be used in a pinch.
Doughnut Cutter
A doughnut cutter makes quick work of punching out a dozen raised doughnuts. Look for one made of stiff metal and with a removable center punch for easier cleaning. If you don't have a doughnut cutter, use a small glass to cut large rounds and punch a hole in the center with your finger, then gently stretch the hole into a 1½-inch-diameter circle.
Non-Terry Towels
When proofing raised doughnuts, a well-floured non-terry towel keeps the dough from sticking and stretching when you pick the doughnuts up to fry. Any non-terry towel is good, but flour sack–type linens work the best.
Heavy-Bottomed Large Pot for Frying
You can use a deep fryer to make doughnuts, but it's not required. Instead, use a heavy-bottomed pot large enough to hold about 1 1/2 liters of oil. You want the oil to be about 2 inches deep and for there to be 2 inches between the surface of the oil and the top of the pot. It's also essential that the pot is heavy-duty; enameled cast-iron Dutch ovens are prefect and do a wonderful job of maintaining consistent oil temperature. A deep fryer offers the advantage of consistent oil temperature, but keep in mind that it requires about twice as much oil as the pot method.
Deep-Fry Thermometer
Also known as a candy thermometer, a deep-fry thermometer is essential for measuring and maintaining a constant oil temperature. Look for one that measures up to 400°F, and has a clip for attaching to the side of the pot. If you use a deep fryer, you won't need a separate thermometer.
Doughnut Pans
If you want to make baked cake doughnuts, you will need to invest in a special doughnut pan to create classic round-bottomed pastries. Doughnut pans can be made of metal or silicone, and both work well. In a pinch, you can substitute a mini-muffin pan, but the doughnuts won't have that characteristic rounded shape.
Doughnut Machine
While far from essential, a doughnut machine offers another way to make cake doughnuts at home. It's similar to a waffle-maker and cooks the whole doughnut with contact heat, so the top and bottom have the same crust texture. If you do invest in a doughnut machine, it's best to use batters that are designed for baking rather than frying.
Making Cake Doughnuts
Cake doughnuts, also known as old-fashioned doughnuts, are leavened with baking powder or baking soda and have a fluffy crumb and a lightly crisp crust. They're made from a thick batter that comes together quickly (no mixer required), and the doughnuts only need a short rest period before they can be fried or baked.
Deep-Frying Cake Doughnuts
Doughnut shops typically fry cake doughnuts and use special doughnut droppers that extrude the batter directly into the hot oil. To mimic this action at home, use a pastry bag to pipe circles of batter onto parchment paper squares, then use the parchment to carefully flip the doughnuts into the hot oil, gently pulling the parchment off the top. Once they're in the hot oil, cake doughnuts will submerge for a few seconds before floating to the surface. Fry them for one to two minutes until the submerged half is golden brown. As the bottom fries, some splitting may occur along the top, but this is nothing to worry about. Once you see the golden brown color along the center of the doughnut, where it hits the oil, gently flip it over with a large slotted spoon—or a chopstick—and continue frying for another one to two minutes until evenly golden brown all over.
Baking Cake Doughnuts
Prefer not to deep-fry? Cake doughnuts are ideal for baking, as long as you follow a recipe specifically designed for the oven. There are baked and fried versions of both cake and yeast doughnuts, but sticking to your recipe's cooking method is important. In other words, avoid frying a baked doughnut recipe and avoid baking a fried doughnut recipe.
