Apple Crisp Cake

Apple crisp cake is the perfect dessert for fall! A moist and tender spice cake filled with brown butter buttercream frosting, apple cinnamon filling, and oat crisp. This cake will put you in the mood for apple picking, sweatshirts, and hayrides.

Ingredients for Apple Crisp Cake

Spice cake

• Unsalted butter: Room temperature.
• Granulated sugar: For sweetness.
• Brown sugar: For molasses flavor.
• Eggs: Room temperature to add moisture and act as a binder.
• Sour cream: Also room temperature for moisture and tang.
• Vanilla extract: Pure vanilla extract or vanilla bean paste adds great flavor.
• Cake flour: Cake flour has less protein than all-purpose flour, creating a tender cake crumb.
• Baking powder: Leavening agent to help the cake rise.
• Salt: Enhances flavors in the cake.
• Cinnamon & nutmeg: Warm spices that are perfect for fall flavors.
• Buttermilk: Room temperature. Regular milk can also be used.

Brown butter buttercream frosting

• Unsalted butter: Room temperature.
• Brown butter: Check out my blog post on how to make brown butter for more info!
• Powdered sugar: For sweetness and structure.
• Vanilla extract: Pure vanilla extract or vanilla bean paste works best.
• Salt: A pinch of salt to add contrast to the sweetness.
• Heavy cream: Brings the buttercream together and helps it whip up to be light and fluffy.

Cinnamon apple filling

• Apples: My favorite are granny smith, pink lady or honeycrisp apples.
• Brown sugar: For sweetness and a bit of molasses flavor.
• Lemon juice: Adds a bit of contrast to the sweetness.
• Cinnamon: Warm spice for flavor.
• Water & cornstarch: Combines to create a slurry to thicken the filling.

Oat crisp

• All-purpose flour: Regular all-purpose flour.
• Brown sugar: For sweetness and molasses flavor.
• Rolled oats: You can also use quick oats.
• Cinnamon: Can’t have enough cinnamon!
• Unsalted butter: Melted.

How to Make Spice Cake

For the spice cake, I recommend using a stand mixer fitted with a paddle attachment or an electric hand mixer for best results.

1. Preheat oven to 335 degrees F and prepare cake pans with nonstick cooking spray and parchment circles. I used 7 inch round pans.
2. On medium speed, cream together butter, sugar, and brown sugar until light and fluffy.
3. Add in eggs one at a time, sour cream, and vanilla extract. Mix until smooth.
4. In a separate bowl, add the cake flour, baking powder, salt, cinnamon and nutmeg, and whisk to combine.
5. On the lowest speed, add the dry ingredients to the butter mixture alternating with the buttermilk: 1/3 dry ingredients, 1/2 buttermilk, 1/3 dry ingredients, 1/2 buttermilk, and 1/3 dry ingredients.
6. Scrape the sides and bottom of the bowl and mix for an additional 30 seconds. Be careful not to overmix the batter!
7. Pour the batter into the prepared cake pans. Use a kitchen scale to create even layers.
8. Bake the cake for approximately 30-35 minutes. This time may vary depending on the size pans you select. You will want to bake the cake layers until an inserted toothpick comes out clean or the cakes bounce back when gently touched.
9. Cool the layers in the pans for about 30 minutes and then remove to a wire cooling rack. After the cake layers are cool, level with a serrated knife.

How to Make Frosting, Filling, and Crisp

Brown butter buttercream frosting

I recommend using a stand mixer with a whisk attachment for the best results. You can also use an electric hand mixer. Check out my recipe blog post for Brown Butter Buttercream Frosting.

1. Whip the butters for 5 minutes until light and fluffy.
2. Add in the powdered sugar in 2 parts, mixing in between each addition.
3. Add the vanilla extract and salt and continue to mix on low.
4. Slowly drizzle in the heavy cream. Scrape the sides and bottom of the bowl to ensure everything is well mixed.
5. Whip the buttercream on medium-high speed until fluffy.
6. (Optional) Switch to a paddle attachment and mix on low speed for an additional 5 minutes to remove air bubbles and made the buttercream silky smooth.

Cinnamon apple filling

1. In a medium saucepan, combine chopped apples, brown sugar, lemon juice, cinnamon, and 1/2 cup water. Mix until combined.
2. Cook the apples over medium heat until the apples begin to soften, approximately 10-15 minutes.
3. Stir together cornstarch and 2 tablespoons of water to create a slurry.
4. Pour the slurry into the apples, turn off the heat, and mix until thickened.
5. Transfer the mixture to a heat-proof bowl and cool to room temperature.

Oat crisp

1. In a bowl, combine flour, brown sugar, oats, cinnamon, and melted butter.
2. Spread the crisp mixture onto a baking pan lined with parchment paper or a silicone baking mat.
3. Bake at 350 degrees for 10 minutes.
4. Remove the crisp from the oven and stir to break it up and return to the oven and bake an additional 10 minutes until crispy.
5. Remove from the oven and allow the crisp to cool on the pan, stirring to break up the pieces.

How to Assemble the Apple Crisp Cake

This is how to assemble the apple crisp cake! It is a standard layer cake process with the addition of the apple cinnamon filling and oat crisp filling. For this recipe, I used three 7-inch cake layers. I recommend using a cake turntable for easy cake decorating.

1. Place one cake layer on an 8 inch round cake board.
2. Add a thin layer of brown butter buttercream frosting onto the cake and spread evenly using an offset spatula.
3. Pipe a ring of buttercream around the outside edge of the cake to create a barrier.
4. Add half of the apple cinnamon filling and spread evenly.
5. Sprinkle on some of the oat crisp on top of the apple filling.
6. Place the next cake layer on top and repeat the above process.
7. Place the final cake layer on the top. Ensure that the cake is even horizontally and vertically. You may need to pipe additional buttercream in between the layers to fill in any gaps.
8. Spread a thin layer of frosting on the top and sides of the cake to create a crumb coat.
9. Chill the cake for 30-60 minutes in the refrigerator.
10. Frost the top and sides of the cake in a thick layer of buttercream using an offset spatula. Smooth with a bench scraper to create smooth sides.
11. Press some of the oat crisp along the bottom of the cake. You may need to pulse the oat crisp in a food processor to make smaller crumbs.
12. Use a Wilton 1M piping tip to decorate and sprinkle with additional oat crisp.