Fluffiest Oat Flour Cake Recipe (Made in 5 Minutes) Recipe
This Fluffiest Oat Flour Cake is a light, airy, and delicious gluten-free dessert made primarily from oat flour and rolled oats. The cake is prepared quickly with minimal fuss, using either a blender or hand mixer for mixing. It’s baked to perfection in an 8×8-inch pan and finished with a smooth and sweet brown sugar frosting that complements the warm cinnamon and oat flavor. Perfect for a simple, wholesome treat that comes together in just about 5 minutes of prep plus baking time, ideal for anyone seeking a gluten-free and comforting homemade cake.
- Prep Time: 10 minutes
- Cook Time: 40 minutes
- Total Time: 50 minutes
- Yield: 9 servings (approximate 3x3 inch squares)
- Category: Dessert
- Method: Baking
- Cuisine: American
- Diet: Gluten Free
Ingredients
Oat Flour Cake
- 2 cups (209 g) gluten-free rolled oats (or 2 cups oat flour)
- ½ cup (100 g) granulated sugar
- ¼ cup (59 g) packed light brown sugar
- 2 tablespoons (18 g) cornstarch
- 1 ½ teaspoons baking powder
- ½ teaspoon baking soda
- 1 teaspoon ground cinnamon
- ¼ teaspoon salt
- 2 large eggs
- ¾ cup (178 g) milk (any preferred type)
- ½ cup (125 g) plain whole milk yogurt
- ¼ cup (48 g) oil (canola or any preferred)
- 2 teaspoons vanilla extract
- ⅓ cup (35 g) old fashioned rolled oats (gluten-free certified)
Brown Sugar Frosting
- 2 tablespoons (28 g) butter
- 2 tablespoons (30 g) light brown sugar
- 1 ¾ cups (210 g) powdered sugar
- 2-3 tablespoons milk
Instructions
- Preheat and Prepare Pan: Preheat your oven to 350ºF (175ºC). Grease an 8×8-inch baking dish thoroughly with nonstick cooking spray to prevent the cake from sticking, then set it aside.
- Make Oat Flour: Using a powerful blender (like a Vitamix), place 2 cups of gluten-free rolled oats and blend for 30-60 seconds until you get a fine powdery oat flour. If you prefer or do not have a blender, use store-bought oat flour.
- Mix Dry Ingredients: To the oat flour in the blender, add granulated sugar, light brown sugar, cornstarch, baking powder, baking soda, ground cinnamon, and salt. Pulse briefly to combine evenly. If using a hand mixer, combine oat flour and dry ingredients in a large bowl and mix on low speed.
- Add Wet Ingredients: Add eggs, milk, plain yogurt, oil, and vanilla extract to the blender. Blend again until smooth, scraping down the sides as necessary. The batter will be thin. For hand-mixing, whisk wet ingredients separately then add to dry ingredients and beat at medium speed until combined; batter should be thin as well.
- Fold in Rolled Oats: Add the remaining ⅓ cup of old fashioned rolled oats to the batter. Pulse a few times if using a blender or mix on low speed if using a hand mixer. Allow the batter to sit for 10 minutes at room temperature to let the oats absorb moisture and help the crumb bind.
- Bake the Cake: Pour the batter into the prepared baking dish and bake in the preheated oven for 38-40 minutes, or until the cake is firm to the touch in the center and a toothpick inserted comes out clean.
- Cool: Remove the cake from oven and place it on a wire rack to cool completely before applying frosting.
- Prepare Frosting: In a medium saucepan over medium-low heat, melt together the butter and light brown sugar, stirring constantly until smooth and combined.
- Add Powdered Sugar and Milk: Remove the saucepan from heat; stir in the powdered sugar and 2 tablespoons of milk. Add an extra tablespoon of milk if needed to achieve desired frosting consistency.
- Frost the Cake: Spread the brown sugar frosting evenly over the completely cooled cake. Slice and serve.
Notes
- Storing Tips: Store leftover cake at room temperature, covered securely with plastic wrap, for up to 3 days. Avoid refrigeration as this can dry the cake out.
- Freezing: You can freeze the cake, frosted or unfrosted. Wrap securely and avoid direct contact between frosting and plastic wrap by freezing first then wrapping. Freeze up to 2 months and thaw at room temperature before serving.
- Baking in Different Pans: For a layer cake, double the ingredients and use two 9-inch round pans. Avoid blending all ingredients at once when doubling; instead blend oats into flour separately then mix by hand.
- Alternate Pan Sizes: A 9×9 or 11×7-inch pan works as well but the cake will be thinner and bake time reduces by 5-10 minutes. For a single layer round cake, use a 9-inch pan lined with parchment paper and grease it. Cool briefly in pan before transferring to a wire rack.
