Sourdough Discard Donuts

Sourdough discard donuts are the best way to turn a cup of leftover starter discard into a cake-style fried donut with crispy edges, a soft tangy interior, and a sweet vanilla glaze. The discard adds depth of flavor and a faint sourdough tang without making the donuts taste sour. If you love sourdough discard recipes, these belong on your weekend breakfast list right next to my sourdough discard pancakes and sourdough pikelets.

Using sourdough discard in your baked goods can add so much depth of flavor and is a great way to use up that discard. From muffins and quick breads to pikelets and pancakes, it can be used in almost any baked good. Sourdough discard isn't used to give rise to these donuts (the baking powder and baking soda do that), it's just an ingredient that adds flavor and texture.

For a classic version without sourdough, my classic baked donut recipe is the one to try.

Jump to:

• Quick Glance at the Recipe: Sourdough Discard Donuts
• What Makes This Sourdough Discard Donut Recipe Different
• Sourdough Discard Donut Ingredients
• Why Oil Temperature Matters (The Science)
• Sourdough Discard Donut Recipe Step-By-Step
• Best Oil, Pot, And Temperature For Frying Donuts
• Donut Topping Options
• Common Sourdough Discard Donut Problems To Avoid
• Make This Sourdough Discard Donut Recipe Your Own
• Make-Ahead, Storage, And Refresh
• Final Thoughts
• Sourdough Discard Donut FAQs
• More Sourdough Discard Recipes To Try
• Leave Me A Review⭐️⭐️⭐️⭐️⭐️
• Recipe

What Makes This Sourdough Discard Donut Recipe Different

Most sourdough discard recipes are quick breakfasts (pancakes, pikelets, muffins). Donuts are a step up: fried, glazed, special-occasion breakfast that uses your discard for something genuinely worth waking up for.

A few things make this version different from most sourdough donut recipes you'll find:

Real frying science. Oil temperature is the difference between bakery-perfect donuts and greasy disappointments. The 360 to 375º F range isn't a suggestion, it's the entire game.

Cake-style, not yeasted. This is a quick donut leavened by baking powder and baking soda, not the long-rise yeasted version some recipes require. The discard adds flavor, not rise. Done in 40 minutes start to finish.

Buttermilk instead of regular milk. The tang of buttermilk amplifies the sourdough discard flavor. If you don't have any on hand, make a buttermilk substitute with a Tablespoon of vinegar in a cup of milk.

Lard for frying. My preferred frying fat. Dairy-free, gives a crisp outer layer and is minimally processed. Vegetable oil and peanut oil work too, full breakdown below.

I used to use a FryDaddy as a kid, I feel like everyone growing up in the 80s and 90s had one! They're super inexpensive and make a great place to store the leftover oil after frying. Just pop the lid back on and store it away until the next use.

Sourdough Discard Donut Ingredients

Nothing surprising here for the ingredients, except I like to use buttermilk instead of regular milk. If you don't have any buttermilk on hand, you can make your own buttermilk substitute. I always recommend weighing your ingredients with a digital kitchen scale for the most accurate results.

• Sourdough discard. A full cup (8 oz). Unfed starter from your fridge or counter. The discard adds flavor and a subtle tang. You can adjust the amount slightly and make up the difference with buttermilk if you have more or less on hand.
• Unsalted butter. Softened to room temperature so it creams properly with the sugar. Cold butter won't whip up fluffy and your donuts will be dense.
• Granulated sugar. Standard white sugar. Sweetens the dough without making the donut itself dessert-level sweet, which leaves room for the glaze.
• Eggs. Two large at room temperature. Cold eggs shock the creamed butter and break the emulsion. If you forgot to take them out, drop them in warm tap water for 5 minutes.
• Buttermilk. Adds tang that complements the sourdough discard. The acid also reacts with the baking soda for extra lift. Whole-milk buttermilk is best.
• Vanilla extract. Real vanilla, not imitation. Just enough to round out the flavor.
• All-purpose flour. Standard AP. Don't substitute bread flour (too tough) or cake flour (too tender for frying).
• Nutmeg. The defining "donut" spice. Freshly grated is best. Don't skip, this is what makes them taste like cake donuts.
• Baking powder and baking soda. Two leaveners working together. Baking soda reacts with the buttermilk and discard for immediate lift. Baking powder gives a second push during frying.
• Salt. Balances the sweetness and amplifies the other flavors.
• Lard (or vegetable oil) for frying. My preferred fat. See the "Best Oil For Frying" section below for the full breakdown of options.
• Powdered sugar + milk for the glaze. Standard donut glaze. Sift the powdered sugar first to avoid lumps.

Why Oil Temperature Matters (The Science)

Oil temperature separates bakery-perfect donuts from greasy ones. Oil temperature controls everything.

Below 360º F: greasy donuts. When the oil is too cool, the donut sits in it longer, trying to cook through. The longer the contact, the more oil gets absorbed. By the time the inside is cooked, the outside has soaked up oil like a sponge. You get a heavy, oily, sad donut.

360 to 375º F: the sweet spot. Hot enough that the surface of the donut immediately starts crisping and forms a barrier that keeps oil OUT, but not so hot that the outside burns before the inside cooks through. The donut puffs, the crust seals, the inside cooks evenly, you drain on a rack, and almost no oil ends up inside.

Above 375º F: burnt outside, raw inside. Surface browns too fast. By the time the outside looks done, the inside is still raw dough. Pull the donut out and the middle slumps.

What drops the temperature? Every time you add a donut to the oil, the oil temperature drops by 10 to 30º F, depending on how cold the donut is and how much oil you have. This is why batch size matters. Fry 2 to 3 donuts at a time, max. If you crowd the pot with 6 donuts, the temperature drops below 350º F, and you're back in greasy territory.

The fix: use a candy thermometer or infrared heat thermometer, check the temperature before every batch, and wait for the oil to recover between rounds. This single habit makes the difference.

Sourdough Discard Donut Recipe Step-By-Step

For exact measurements, see the recipe card below.

Before you start: All refrigerated ingredients (eggs, buttermilk, butter) need to be at room temperature so they combine properly. Set them out an hour ahead, or warm the eggs in warm tap water for 5 minutes and microwave the butter in 10-second bursts until soft.

PRO TIP: Fry 2 to 3 donuts at a time MAXIMUM. Every donut you add drops the oil temperature by 10 to 30º F. Crowd the pot, and the temperature plummets below
350º F, and your donuts will absorb oil. Smaller batches, hotter oil, perfect texture.

Best Oil, Pot, And Temperature For Frying Donuts

Three equipment / setup decisions that make or break frying.

Best oil

The best oil for deep frying has a high smoke point and a neutral flavor. The three workhorses, ranked by my preference:

Vegetable oil or peanut oil. Lowest saturated fat, but leaves an unpleasant lingering taste on fried foods and in the air. Acceptable substitute if you don't want to keep lard around.

Lard (my preferred). Neutral flavor, dairy-free, creates a very crisp outer layer on the donuts, and minimally processed. See my cake donut recipe for more on lard.

Crisco (vegetable shortening). Neutral flavor but made from soybean oil, fully hydrogenated palm oil, and some additives including trans fats in small amounts.

Best pot

A heavy pot with high sides is the safest setup. A Dutch oven works. A FryDaddy regulates temperature for you and doubles as oil storage between uses. Whatever you use, never fill more than half full of oil. You only need about 2 inches of oil to fry donuts.

Best temperature

Aim for the sweet spot of 360 to 375º F (182 to 190º C). Use a candy thermometer or an infrared heat thermometer. Check every batch before. Wait for the temperature to recover after adding donuts. See the science section above for what happens outside this range.

Donut Topping Options

Sourdough donuts aren't very sweet on their own, so the glaze does the work. Three options:

• Classic glaze. Combine 1 cup sifted powdered sugar with 2 Tablespoons of milk (or water) and whisk smooth. Dunk the top of each warm donut.
• Powdered sugar. Roll the warm donut in powdered sugar. Simplest finish.
• Cinnamon sugar. Combine 1 cup of granulated sugar with 2 teaspoons of cinnamon. Roll while still warm so the sugar sticks.

Glaze variations (start with the classic glaze and add):

• Vanilla glaze. Add ½ teaspoon vanilla extract.
• Cinnamon glaze. Add 1 teaspoon of cinnamon.
• Maple glaze. Replace the milk with maple syrup.
• Lemon glaze. Replace the milk with fresh lemon juice + 1 teaspoon lemon zest.
• Orange glaze. Replace the milk with fresh orange juice + 1 teaspoon orange zest.
• Chai glaze. Add 1 teaspoon of chai spice mix (cinnamon, cardamom, ginger, cloves, black pepper).
• Chocolate glaze. Replace 2 Tablespoons of the powdered sugar with cocoa powder.

Common Sourdough Discard Donut Problems To Avoid

• Donuts are greasy and oily. Oil temperature was too low. The donut sat in cool oil too long and absorbed it. Use a thermometer. Wait for oil to recover between batches.
• Donuts are burnt outside and raw inside. Oil temperature was too high. Drop the heat. The sweet spot is 360 to 375º F, not "as hot as possible."
• Donuts are dense and don't puff. Either the dough was overworked (added too much flour during shaping, or kneaded too long) or your leaveners are old. Check the dates on your baking soda and baking powder. They die after about 6 months opened.
• Dough is too sticky to roll. Normal. Don't add a ton of extra flour, which makes tough donuts. Use a bench scraper to handle, dust your hands and surface lightly, and chill the dough 10 minutes if it's really unmanageable.
• Dough is too dry and cracking when rolled. Too much flour worked in during shaping. A little water on your hands and gentle re-pressing usually fixes it.
• Glaze cracks or breaks off after a few hours. Glaze was too thick or applied to hot donuts. Aim for the consistency of warm honey, and let donuts cool to warm-but-not-hot before glazing.
• Donuts are soggy after a day. Storage issue. Open container at room temp (paper bag or partially-vented plastic) keeps them crisper than sealed plastic. Refresh in a 300º F oven for 3 minutes to revive the crisp.

Make This Sourdough Discard Donut Recipe Your Own

• Donut holes. When you cut the donuts, save the centers. Fry them at the end of your batch for about 1 minute, stirring and pushing them down with your spoon. Yields about 12 holes per recipe.
• Mini donuts. Use a 2 inch ring cutter instead of 4 inch. Fry for 1 minute per side. Doubles your yield to 24 mini donuts, perfect for a brunch board.
• Active starter swap (for true sourdough donuts). Use 1 cup of active, recently-fed sourdough starter instead of discard. Donuts will have a touch more rise (the active yeast adds extra lift on top of the leaveners) and a milder tang. Same method, same fry time. The "discard version" is the everyday default because it uses up what would otherwise be waste.
• Cinnamon-sugar coated. Skip the glaze entirely. Toss the warm donuts in a mixture of 1 cup sugar + 2 teaspoons cinnamon. Classic apple-cider-donut style without the apple cider.
• Filled donuts. Cut the dough into rounds (no holes), fry, cool, then use a piping tip to inject pastry cream, jam, or lemon curd. Roll the outside in powdered sugar.
• Why I don't have a baked version. I tested baking and air-frying this recipe during development. The texture came out dry and hard, nothing like a real cake donut. The structure relies on the quick hit of hot oil to puff and crisp the outside. For a baked cake donut, you need a recipe formulated for the oven, like my classic baked donut recipe.

Make-Ahead, Storage, And Refresh

Cake donuts are best the day they're made, but they store fine for a few days with the right setup.

• Cooked donuts at room temperature. Paper bag or partially-vented plastic, up to 3 days. The crispy outer layer softens after 24 hours.
• Cooked donuts in the freezer. Flash-freeze unglazed donuts in a single layer for 1 hour, then bag. Up to 2 months. Thaw at room temperature for 1 hour, then refresh and glaze.
• Refresh stale donuts. 300º F oven for 3 minutes brings back most of the crisp. Glaze AFTER refreshing.
• Sourdough discard. Cover and refrigerate up to 1 week before using for this recipe.

Final Thoughts

Cake donuts are the kind of weekend project that makes the kitchen feel like a real bakery. Hot oil, cinnamon sugar in the air, a rack of glazed donuts cooling next to the stove. The sourdough discard adds depth of flavor and gives you a real reason to keep that starter alive even on weeks when you don't bake bread. EASY!

If you love these and want the cluster, see my sourdough discard pancakes for the weekday breakfast version, sourdough pikelets for the savory-friendly small bite, and sourdough discard crackers for the snack version.

If donuts feel like too much frying for a slow weekend, my sourdough discard cinnamon roll recipe is the oven-baked alternative that uses a full cup of discard with cream cheese frosting.

Sourdough Discard Donut FAQs

More Sourdough Discard Recipes To Try

If you love these donuts, here's the rest of the sourdough cluster on SGS to make use of your discard.

Recipe