Easy & Fudgy Birthday Cake Brownies

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These Birthday Cake Brownies are an easy made from scratch dessert to celebrate any occasion. A layer of funfetti cookies topped with fudgy brownies and mixed with sprinkles and mini chocolate chips bakes into a delicious surprise of flavors and textures.

Birthday cake brownies topped with sprinkles and cut into squares.

Why eat traditional cake for your birthday when you can eat birthday cake brownies? These aren’t plain old brownies. They’re a layer of chewy funfetti cookie topped with fudgy brownie and, of course, extra sprinkles and mini chocolate chips mixed in.

Sure, everyone loves birthday cupcakes and fudgy cake, but these brownies are so easy to make (from scratch!). They're a fun alternative to a classic cake, just like my stuffed birthday cake cookies.

As a busy mom of three, a quick treat is a go-to for our family. No need to wait to celebrate a birthday to make these brownies, they’re the perfect treat to satisfy a sweet craving!

Why You'll Love This Recipe

Combination of two favorites. These brownies combine two favorite flavors, funfetti cookies and fudgy brownies with extra sprinkles and mini chocolate chips sprinkled throughout.
Alternative to birthday cake. Non-cake lovers will rejoice with these brownies. They are a festive and fun alternative to birthday cake.
Quick & easy to make. Birthday cake brownies are easy to make from scratch (no box mixes necessary!) in just 45 minutes.

Ingredients You'll Need

All-purpose flour. Provides the structure in both layers of these brownies. Using all-purpose gives the right amount of tenderness and structure.
Baking soda. The leavening agent in the cookie layer helps them rise during baking.
Salt. A little goes a long way. Salt helps enhance the sweetness of these brownies.
Sugar. Adds sweetness and moisture to both layers of these birthday cake brownies.
Eggs. Helps hold the ingredients together. They also contribute moisture to both layers in these brownies.
Egg yolk. Helps create a light and chewy cookie texture. The extra fat also enriches the flavor.
Vanilla. Always select a good quality pure vanilla extract for the best flavor.
Butter. Use unsalted butter to control the amount of salt that goes into the recipe. Melting the butter contributes to the chewy texture of the cookie and brownie layers.
Sprinkles. Rainbow sprinkles are so fun and fitting for birthdays! Stick with sprinkles (aka jimmies). Nonpareils will bleed into your cookie dough during baking.
Semi-sweet chocolate bar. Adds a rich flavor to brownies. It’s the preferred choice for its higher quality and better results compared to chocolate chips.
Cocoa powder. Using unsweetened cocoa powder adds a rich flavor to the brownie layer. If you have Dutch-processed cocoa powder on hand, you can use that instead.
Cornstarch. Add to the brownie batter to produce a thicker consistency and to improve the shiny crust on top.
Mini chocolate chips. Adds texture to the brownie layer for a fun little surprise.

How to Make This Recipe (step-by-step)

Mixing bowl with wet ingredients for cookie dough.

Whisk dry and wet ingredients separately. Whisk together the cookie batter dry ingredients and set aside. In a separate bowl, whisk together the sugar, egg, egg yolk, and vanilla until the mixture becomes light and creamy. Add the melted butter and combine.

Add dry ingredients. Fold the dry ingredients and sprinkles into the butter mixture until combined.

Mixing bowl with whisked eggs and sugar for brownie batter.

Prepare brownie batter. Melt the chocolate and butter together until completely smooth. Whisk the sugar and egg together constantly for 2-3 minutes until pale in color.

Mixing bowl with brownie wet ingredients.

Combine chocolate and egg mixtures. Add the melted chocolate to the sugar and egg mixture and combine.

Add dry ingredients. Gently fold in the dry ingredients along with the mini chocolate chips.

Add cookie batter to pan. Scoop the cookie batter into a parchment-lined 8x8-inch square pan, leaving spaces between each scoop.

Baking pan with birthday cake brownie batter.

Add brownie batter. Pour the brownie batter into the pan to fill the gaps and spread it into an even layer with an offset spatula. Sprinkle with the sprinkles and mini chocolate chips and bake for 25 to 28 minutes.

Note: Whisking the eggs and sugar together until thickened and a pale yellow color is referred to as the “ribbon stage”. The mixture will fall from the whisk like ribbons. This technique creates taller and creamier brownies with a shiny crust.

Baking Success Tips and Takeaways

Scale ingredients. Use a kitchen scale to measure your ingredients for consistent results. Using cup measurements can cause variations in ingredients, and too much flour will result in a more cakey brownie and a less fudgy brownie.
Metal or glass pan. Use a metal or glass 8x8-inch square baking pan for even baking. A dark coated pan can cause your brownies to overbake.
Parchment paper lined pan. Line your baking pan with parchment paper so that it hangs over the edges. Your brownies won’t stick and it will be easy to lift the brownies from the pan.
Use sprinkles. Rainbow or any color sprinkles work best in these birthday brownies. I avoid using nonpareils as they can bleed into the batter.
Cool completely. Allow the birthday brownies to cool completely before slicing. It’s important for the chocolate and butter to resolidify.

Recipe Substitutions

As a trained pastry chef, when baking I’ve learned that it’s not always simple to make substitutions to recipes. But here are two substitutions that can easily be made to your brownies.

Substitute brown sugar for the granulated sugar in the brownie batter for an even fudgier brownie.
For this recipe, Dutch-process cocoa powder can be substituted for unsweetened (natural) cocoa powder. This substitution will result in darker brownies with an even more intense chocolate flavor.

Recipe Variations

Birthday cake brownies are such a festive dessert to serve. Here are some ideas for tweaking this recipe to your preferences and how to serve it!

Make birthday cake oreo brownies. Add a layer of crushed Golden Oreos between the cookie and brownie layers for a fun surprise.
Serve a la mode. Slice the birthday cake brownies into bars and serve warm topped with vanilla ice cream.
Brown butter cookie layer. Switch it up with brown butter chocolate chip cookie dough in place of the funfetti layer for the chocolate lovers in your life!

Storage Tips

To store. Keep these funfetti brownies stored in an airtight container for up to 3 days at room temperature or refrigerated for up to 1 week.

To freeze. Store leftovers in an airtight container or freezer-safe bag and freeze for up to 3 months. When ready to enjoy, thaw in the refrigerator overnight.

FAQ

Can I double this recipe?

Yes, you can bake these birthday cake brownies in a 9x13-inch rectangular baking pan. Increase the time slightly to account for the extra batter.

Do birthday cake brownies need to be refrigerated?

No, these brownies can be stored covered at room temperature for up to 3 days.

What's the difference between fudgy and cakey brownies?

Fudgy brownies have a more dense and chewy texture. They are rich and sometimes even gooey. Fudgy brownies typically use more butter which is melted with the chocolate. Cakey brownies are lighter and more cake-like and are typically made with creaming the butter and sugar.

More Birthday Recipes You'll Love

Please leave a starred rating and comment below if you make these Birthday Cake Brownies. I love reading your feedback! And if you'd like to make this recipe later, don't forget to pin it on Pinterest! Happy Baking!