These double chocolate oat-bottom brownies are a triple-layered delight: a buttery oatmeal base, a chewy chocolate brownie center, and a soft white chocolate topping. This easy bar cookie recipe is simple to make and even easier to enjoy.
I always appreciate a homemade brownie or bar recipe that comes together quickly and doesn’t require chilling or shaping individual cookies. These oat-bottom brownies fit that bill perfectly—easy prep, straightforward baking, and the kind of treat you won’t want to stop eating.
The three layers each contribute texture and flavor: a rich, buttery oat base, a fudgy chocolate middle, and a smooth white chocolate topping that sets like a soft fudge. These bars are comforting, satisfying, and ideal for sharing—though you might be tempted to keep them all to yourself.
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Let’s make this easy, homemade, triple-layer brownie!
Begin by combining quick oats, all-purpose flour, brown sugar, and baking soda in a medium bowl. Stir in the melted butter until the mixture holds together, then press it evenly into the bottom of a parchment-lined 9×9-inch baking pan. Bake this oat layer for 10 minutes to set the base.
While the oat layer bakes, prepare the brownie layer. Whisk the dry ingredients—flour, baking powder, and salt—in a small bowl. In another small bowl or cup, combine milk and vanilla. In a separate mixing bowl, beat together the granulated sugar, melted butter, melted and cooled chocolate, and one large egg until smooth. Add half of the dry mixture, then the milk-vanilla mixture, followed by the remaining dry ingredients. Whisk until just combined, then pour the batter over the partially baked oat base and bake for about 25 minutes more. Let the pan cool completely before adding the white chocolate topping.
How to make the white chocolate topping
The final layer is a white chocolate, fudge-like topping that adds extra sweetness and a creamy finish. To make it, melt white chocolate and butter together over low heat in a small saucepan, stirring constantly. Once smooth, add powdered sugar and vanilla—the mixture will thicken and become lumpy. Stir in two tablespoons of hot water to loosen the mixture; it will transform into a smooth, pourable white chocolate sauce.
Pour the white chocolate mixture evenly over the cooled brownie layer and allow it to set completely. This can take several hours at room temperature. When fully set, lift the bars from the pan using the parchment paper and cut them into squares or bars of your preferred size.
How to store double chocolate oat-bottom brownies
Store the bars in an airtight container at room temperature for 5–7 days. If you prefer a firmer topping, you can chill them briefly before serving, but they are best enjoyed at room temperature when the white chocolate layer has a soft, fudge-like texture.
Looking for more easy bar recipes?
- Addictive Peanut Butter Bars
- Mom’s Lemon Bars
- Pumpkin Caramel Spice Bars
- Sunbutter and Jelly Bars
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Double Chocolate Oat Bottom Brownies
A triple-layered treat with an oatmeal base, a chocolate brownie middle, and a soft white chocolate topping.
20 minutes
35 minutes
55 minutes
Ingredients
Oat layer
- 1 cup quick oats
- ½ cup all-purpose flour
- ½ cup brown sugar
- ¼ teaspoon baking soda
- 6 tablespoons unsalted butter, melted
Brownie layer
- ¾ cup granulated sugar
- ¼ cup unsalted butter, melted
- 1 ounce chocolate (semi-sweet or milk), melted and cooled
- 1 large egg
- ⅔ cup all-purpose flour
- ¼ teaspoon baking powder
- ¼ teaspoon salt
- ¼ cup milk
- 1 teaspoon pure vanilla extract
White chocolate fudge layer
- 1 ounce white chocolate
- 2 tablespoons unsalted butter
- 1 cup powdered sugar
- 1 teaspoon vanilla
- 2 tablespoons hot water
Instructions
- Preheat the oven to 350°F (175°C).
- In a medium bowl, combine quick oats, flour, brown sugar, and baking soda. Stir in melted butter until combined. Press the oat mixture into the bottom of a parchment-lined 9×9-inch baking pan. Bake for 10 minutes.
- For the brownie layer, whisk together the flour, baking powder, and salt. In a small cup, mix the milk and vanilla.
- In a separate bowl, whisk the granulated sugar, melted butter, melted chocolate, and egg until smooth. Add half of the dry mixture, then the milk-vanilla, followed by the remaining dry ingredients. Pour over the baked oat layer and bake an additional 25 minutes. Allow to cool completely before adding the white chocolate topping.
- To make the white chocolate fudge layer, melt white chocolate and butter over low heat, stirring constantly. Remove from heat, stir in powdered sugar and vanilla—the mixture will be thick and clumpy. Stir in 2 tablespoons of hot water until smooth, then pour over the cooled brownies. Allow to set completely.
- Lift the bars from the pan using the parchment and cut into desired sizes. Enjoy!
Notes
Store bars in an airtight container at room temperature for up to 5–7 days.
Nutrition Information:
Yield:
16
Serving Size:
1
Amount Per Serving:
Calories: 237Total Fat: 11gSaturated Fat: 6gTrans Fat: 0gUnsaturated Fat: 4gCholesterol: 36mgSodium: 84mgCarbohydrates: 34gFiber: 1gSugar: 24gProtein: 2g
The nutrition information is an estimate and may not be entirely accurate.
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