Sourdough Apple Crisp with Oat Crumble Topping

This easy sourdough apple crisp is made with fresh sliced apples, cinnamon, brown sugar, and a buttery oat crumble topping with sourdough discard mixed right in. It has all the comfort of an old-fashioned apple crisp recipe, but the sourdough discard gives the topping a little extra depth without making the dessert taste sour.

I like this recipe because it is simple, practical, and perfect for apple season. If you are looking for more ways to use fresh apples, you may also like my Best Fall Apple Recipes to Make With Fresh Apples or this Cinnamon Apple Crumble Sourdough Quick Bread Recipe.

This sourdough discard apple crisp is not a long fermented recipe or a complicated sourdough project. It is just a simple homemade apple crisp with oats, butter, brown sugar, and discard added to the crumble topping. The apples bake until tender and bubbling, and the topping turns golden, crisp, and buttery.

Serve it warm with a scoop of homemade vanilla bean ice cream, and it is one of the easiest fall apple desserts to make from scratch.

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Quick Look

Prep Time: 20 minutes
Bake Time: 35 to 45 minutes
Total Time: 55 minutes to 1 hour 5 minutes
Servings: 6 to 8
Texture: Tender cinnamon apples with a buttery crisp oat topping
Best Served: Warm, with vanilla ice cream if desired

What Is Sourdough Apple Crisp?

Sourdough apple crisp is a homemade apple crisp made with sourdough discard in the crumble topping. The apple filling is still classic and simple, with fresh apples, brown sugar, cinnamon, lemon juice, vanilla, and a little flour to help thicken the juices.

The sourdough discard goes into the oat crumble topping with flour, oats, brown sugar, cinnamon, salt, and butter. It helps bring the topping together and gives the crisp a slightly deeper flavor.

This is still very much an easy apple crisp recipe. The sourdough discard does not make it complicated, and it does not need a long rest or fermentation time.

Why You’ll Love This Sourdough Apple Crisp

This apple crisp is made with fresh apples and simple pantry ingredients.

It is a good way to use sourdough discard without making bread.

The oat crumble topping is buttery, crisp, and generous.

The apple filling is warm, cinnamon-spiced, and not overly fussy.

It is a simple fall dessert that works for family dinners, Sunday supper, Thanksgiving, or apple picking season.

It tastes especially good served warm with vanilla ice cream.

Equipment You Will Need

8x8 or 9x9 baking dish

Large mixing bowl

Medium mixing bowl

Peeler

Sharp knife

Cutting board

Measuring cups and spoons

Kitchen scale, optional

Rubber spatula or wooden spoon

Pastry cutter or fork, optional

Ingredients for Sourdough Apple Crisp

Apple Filling

• 6 cups peeled and sliced apples (about 700 grams)
• ⅓ cup packed brown sugar (about 70 grams)
• 1 tablespoon all-purpose flour or freshly milled soft white wheat flour (9 grams)
• 1 tablespoon lemon juice
• 1 teaspoon ground cinnamon
• ¼ teaspoon ground nutmeg
• ¼ teaspoon salt
• 1 teaspoon vanilla extract

Sourdough Oat Crumble Topping

• ¾ cup all-purpose flour or freshly milled soft white wheat flour (107 grams)
• ¾ cup old-fashioned rolled oats (about 68 grams)
• ½ cup packed brown sugar (about 105 grams)
• ½ teaspoon ground cinnamon
• ¼ teaspoon salt
• ½ cup unsalted butter, softened or melted and cooled (113 grams)
• ⅓ cup sourdough discard (about 75 grams)

Using Freshly Milled Wheat Flour

Freshly milled soft white wheat flour can be substituted for the all-purpose flour in an equal 1:1 swap by weight. Soft white wheat has a mild flavor and tender texture that works especially well in crumble toppings. The freshly milled flour may absorb moisture a little differently, so allow the topping to rest for about 5 minutes after mixing before adding it to the apples. Hard white or hard red wheat flour can also be used, but they will create a slightly heartier topping.

Best Apples to Use for Apple Crisp

The best apples for apple crisp are apples that hold some shape while baking. You want them tender, but not completely mushy.

Good options include:

Honeycrisp

Granny Smith

Braeburn

Pink Lady

Jonathan

Golden Delicious

Fuji

A mix of sweet and tart apples gives the best flavor. If your apples are very sweet, you can keep the sugar as written. If your apples are very tart, the brown sugar helps balance them.

How to Make Sourdough Apple Crisp

Preheat the oven to 375°F. Lightly grease an 8x8 or 9x9 baking dish. Peel, core, and slice the apples. Try to keep the slices close in size so they bake evenly.

Add the sliced apples to a large mixing bowl. Add the brown sugar, flour, lemon juice, cinnamon, nutmeg, salt, and vanilla extract.

Stir until the apples are evenly coated.

Spread the apple filling into the prepared baking dish.

In a medium mixing bowl, add the flour, oats, brown sugar, cinnamon, and salt. Stir to combine.

Add the softened butter or melted and cooled butter. Add the sourdough discard.

Mix until the topping comes together and looks crumbly. It should be moist enough to clump together in places, but still easy to scatter over the apples.

Sprinkle the sourdough oat crumble topping evenly over the apple filling. Bake at 375°F for 35 to 45 minutes, or until the apple filling is bubbling around the edges and the topping is golden.

Let the apple crisp cool for at least 10 to 15 minutes before serving. The filling will thicken a little as it cools. Serve warm with vanilla ice cream, whipped cream, or a drizzle of cream.

Tips for the Best Apple Crisp

Slice the apples evenly so they bake at the same rate.

Do not skip the lemon juice. It brightens the flavor and helps balance the sweetness.

Use old-fashioned rolled oats for the best oat crumble topping.

Bake until the filling bubbles around the edges. This is how you know the apples are hot enough and the filling has thickened.

If the topping is browning too quickly but the apples are not tender yet, loosely cover the dish with foil and continue baking.

Let the apple crisp rest before serving. The filling will be very hot when it comes out of the oven and will thicken slightly as it sits.

Serving Ideas

This sourdough apple crisp is best served warm.

You can serve it plain, but I think apple crisp is especially good with a scoop of French Vanilla Ice Cream melting over the warm apples and crisp oat topping.

It is also good with whipped cream, a drizzle of heavy cream, or a little homemade caramel sauce if you want something extra.

For a simple fall dessert table, serve it with coffee, hot tea, or warm apple cider.