Birthday Sheet Cake

5 from 1 vote

This Birthday Sheet Cake takes the iconic chocolate yellow cake flavor and turns it into something totally foolproof and easy to make! A rich, buttery vanilla cake with a layer of rich chocolate cream cheese frosting, topped with sprinkles to make it extra special for celebrations!

Prep Time30

Cook Time30

Cooling time1

Total Time2

Course: Dessert

Cuisine: American

Diet: Vegetarian

Servings: servings

Calories: 677kcal

Author: Briana

Equipment

oven thermometer
9x13 baking pan
hand mixer or stand mixer with a paddle attachment
digital food scale

Ingredients

Cake

2 cups all-purpose flour 272g
1 tablespoon baking powder
½ teaspoon baking soda
1.5 teaspoons kosher salt
1 cup unsalted butter softened at room temperature 16 tablespoons
1 ½ cups white sugar 300g
2 large eggs room temperature
1.5 tablespoons vanilla extract
½ cup sour cream 120g, room temperature
1 cup whole milk 240ml, room temperature

Chocolate cream cheese frosting

8 ounces cream cheese 1 full-fat block, room temperature
¾ cup unsalted butter 12 tablespoons, room temperature
5 ounces semi-sweet chocolate melted and cooled
1 teaspoon kosher salt
1 tablespoon vanilla extract
2-3 cups powdered sugar sifted, as needed and to taste
¼ cup Dutch processed cocoa powder 24g

Instructions

Cake

Preheat oven to 350°F. Grease a 9×13-inch baking pan really well. We also like to add parchment paper so we can easily remove the cake from the pan, later.
In a small bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
2 cups all-purpose flour, 1 tablespoon baking powder, ½ teaspoon baking soda, 1.5 teaspoons kosher salt
In a separate large bowl, or in a stand mixer with a paddle attachment, beat the butter and sugar together on high-speed for a few minutes until smooth. Make sure to scrape the sides of the bowl as needed to ensure everything is incorporated.
1 cup unsalted butter, 1 ½ cups white sugar
Add in the eggs and vanilla, and cream together until combined on medium speed. Then, mix in the sour cream until combined.
2 large eggs, 1.5 tablespoons vanilla extract, ½ cup sour cream
Add half of the dry ingredients and half of the milk and beat on low speed until combined. Add the rest of the dry ingredients and milk and beat on low speed until combined. Do not overmix, mix until just completely combined, ensuring that you scraped the sides. The batter will be thick. We commend switching to a whisk or rubber spatula to ensure everything is well incorporated without overmixing.
1 cup whole milk
Spread the cake batter into your prepared pan. Smooth it out into an even layer.
Bake the cake for 25-30 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean. Rotate the pan a couple of times during baking to ensure it cooks evenly. While the cake cools, make the frosting.

Frosting

In a large bowl, cream together the cream cheese and butter until smooth and combined, and no lumps remain.
8 ounces cream cheese, ¾ cup unsalted butter
Add melted and slightly cooled chocolate, vanilla extract, and salt. Mix to combine.
5 ounces semi-sweet chocolate, 1 teaspoon kosher salt, 1 tablespoon vanilla extract
Sift in powdered sugar and cocoa powder to avoid any large chunks of powder in the frosting. We also recommend adding less of the powdered sugar to start, and then adding more to taste as needed! Continue mixing until totally combined, making sure to scrape the sides and the bottom of the bowl to ensure everything is incorporated.
2-3 cups powdered sugar, ¼ cup Dutch processed cocoa powder

Assemble and enjoy!

When the cake is cooled off, use an offset spatula, (or just a large spoon!) to frost the cake. Top with sprinkles if desired. Enjoy!
Store leftovers in an airtight container in the fridge for up to 5 days. Allow it to sit out at room temperature for 20-30 minutes before enjoying it again to let the cake and frosting soften a bit.

Notes

Use room temperature ingredients. This ensures that the cake batter will come together evenly.
Weigh ingredients with a kitchen scale. Not only does this mean fewer dishes for you (score!) but it also means a much more accurate result. If your cake is too dry or dense
Don't overmix the batter. Make sure to mix until combined, and be sure to scrape the sides of the bowl, but don't overmix! Adding the milk and dry ingredients half at a time helps ensure things get well incorporated, but not overmixed. This is also why we recommend switching to a rubber spatula near the end of mixing.
Don't overbake. Watch the cake, and the oven temperature closely. Use an oven thermometer to ensure the oven isn't too hot, and be sure to rotate the pan a few times to keep an eye on it and ensure even baking.
When making the frosting, take the time to cream together the butter and cream cheese first. This will ensure the frosting is nice and smooth without lumps.
Make sure the chocolate isn't too hot when adding to the frosting. Allow it to cool slightly.
Sift in powdered sugar and cocoa powder. This ensures you don't have lumps in your frosting!
Let the cake cool completely before frosting. If you try to put frosting on a warm cake, it will just slide off and become a greasy mess, so try your best to just wait it out!

Nutrition