Birthday Cake Brownies

5 from 5 votes

These birthday cake brownies are a funfetti cake baked in a 9X9-inch pan topped with brownie batter that is swirled in. You get both sprinkle cake and brownie batter all in one!

Prep Time40

Cook Time35

Total Time1 15

Servings: bars

Calories: 228kcal

Ingredients

Funfetti Cake

1 ¾ cup All-purpose flour
½ tablespoon Baking powder
½ teaspoon Salt
½ cup Unsalted butter room temperature
¾ cup White granulated sugar
¼ cup Sour cream room temperature or plain yogurt
½ tablespoon Clear imitation vanilla see notes
2 Large eggs room temperature
½ cup Buttermilk room temperature
⅓ cup Rainbow jimmie sprinkles

Brownie Batter

½ cup White granulated sugar
1 Large egg room temperature
2 tablespoon Unsalted butter melted
2 tablespoon Oil canola or vegetable
1 teaspoon Pure vanilla extract
3 tablespoon All-purpose flour
¼ cup Unsweetened cocoa powder
½ tablespoon Cornstarch
½ teaspoon Salt
¼ cup Semi-sweet chocolate chips

Vanilla Glaze

½ cup Powdered sugar
1 tablespoon Milk
1 teaspoon Pure vanilla extract

US Customary - Metric

Instructions

Funfetti Cake

Preheat the oven to 350°F. Spray a 9X9-inch pan with baking nonstick spray. Line the bottom of the pan with parchment paper. Spray again.
In a medium bowl, mix the flour, baking powder, and salt. Set aside.
1 ¾ cup All-purpose flour, ½ tablespoon Baking powder, ½ teaspoon Salt
Using a mixer, beat the butter and sugar on high speed for 3 minutes. The butter should be light and fluffy.
½ cup Unsalted butter, ¾ cup White granulated sugar
Then, add in the sour cream, vanilla, and eggs. Mix on medium until combined. You will need to scrape the bowl with a rubber spatula to make sure it is all combined.
¼ cup Sour cream, ½ tablespoon Clear imitation vanilla, 2 Large eggs
Add ⅓rd of the dry ingredients and half of the buttermilk and mix on low speed. Add another ⅓rd of the dry ingredients and the rest of the buttermilk. Then, finish with the rest of the dry ingredients.
½ cup Buttermilk
Take off the mixer and fold in the sprinkles. Spread the cake batter evenly into the prepared pan.
⅓ cup Rainbow jimmie sprinkles

Brownie Batter

In a small bowl, mix the flour, cocoa powder, cornstarch, and salt. Set aside. Using a mixer with a whisk attachment, beat the sugar and egg on high speed for 5 minutes.
½ cup White granulated sugar, 1 Large egg, 3 tablespoon All-purpose flour, ¼ cup Unsweetened cocoa powder, ½ tablespoon Cornstarch, ½ teaspoon Salt
Add in the melted butter, oil, and vanilla and mix on low until just combined. Add in the dry ingredients and mix until mostly combined.
2 tablespoon Unsalted butter, 2 tablespoon Oil, 1 teaspoon Pure vanilla extract
Take off the mixer and mix use a rubber spatula to scrape the bowl. Then, add in the chocolate chips.
¼ cup Semi-sweet chocolate chips
Use a Tablespoon to scoop the batter on top of the cake. Place it in spread out dollops. Use a butter knife to swirl in the batter.
Bake for 30-35 minutes until a took pick inserted comes out clean with cake crumb, but moist crumbs for brownie batter. If the brownie part looks like raw batter, bake for another 3-4 minutes.
Let the cake sit in the hot pan for 10 minutes. Then, transfer to a cooling rack. Cool completely before decorating

Vanilla Glaze

In a small bowl, mix the powdered sugar, vanilla, and milk. Lightly drizzle the glaze on top of the cake. I also topped it with more sprinkles.
½ cup Powdered sugar, 1 tablespoon Milk, 1 teaspoon Pure vanilla extract

Notes

Clear vanilla extract: This gives it a sweeter vanilla taste. You can also use pure vanilla extract instead.

Flour- Make sure flour is spooned and leveled or use a kitchen scale. Compacted flour can dry out the cake.

High altitude baking- Add an extra 1 tablespoon of flour.

Pull out dairy ingredients 2 hours before baking.

Nutrition