Milk Bar Birthday Layer Cake (Printable)
Nostalgic vanilla layer cake with creamy frosting, rainbow sprinkles, and crunchy crumb topping.
# What You’ll Need:
→ Cake
01 - 2 1/2 cups cake flour
02 - 1 1/2 teaspoons baking powder
03 - 1/4 teaspoon baking soda
04 - 3/4 teaspoon kosher salt
05 - 1/2 cup unsalted butter, at room temperature
06 - 1/3 cup vegetable shortening, at room temperature
07 - 1 1/4 cups granulated sugar
08 - 1/4 cup light brown sugar, packed
09 - 3 large eggs
10 - 1/2 cup buttermilk, at room temperature
11 - 1/3 cup whole milk
12 - 2 teaspoons clear vanilla extract
13 - 1/4 cup rainbow sprinkles
→ Birthday Cake Crumb
14 - 1/2 cup cake flour
15 - 1/2 cup granulated sugar
16 - 2 tablespoons light brown sugar, packed
17 - 3/4 teaspoon baking powder
18 - 1/4 teaspoon kosher salt
19 - 2 tablespoons rainbow sprinkles
20 - 1/4 cup unsalted butter, melted
21 - 1 tablespoon clear vanilla extract
→ Frosting
22 - 1 cup unsalted butter, at room temperature
23 - 1/4 cup vegetable shortening, at room temperature
24 - 2 ounces cream cheese, softened
25 - 1 tablespoon clear vanilla extract
26 - 1/4 teaspoon kosher salt
27 - 3 cups powdered sugar, sifted
28 - 1 to 2 tablespoons whole milk
→ Assembly
29 - 1/4 cup whole milk
30 - 1 teaspoon clear vanilla extract
# How-To Steps:
01 - Preheat oven to 350°F. Grease a quarter sheet pan (9x13 inches) and line with parchment paper.
02 - Whisk together cake flour, baking powder, baking soda, and salt in a bowl. Using a stand mixer, beat butter, shortening, and sugars on medium-high speed until light and fluffy, 2–3 minutes. Scrape down bowl. Add eggs one at a time, beating well after each addition. Reduce mixer speed; add buttermilk, milk, and vanilla extract. Mix until combined. On low speed, add dry ingredients and mix just until incorporated. Fold in rainbow sprinkles.
03 - Pour batter into prepared pan and smooth top. Bake for 28–32 minutes until a toothpick inserted into center comes out clean. Cool completely in pan.
04 - Lower oven temperature to 300°F. In a bowl, combine flour, granulated sugar, brown sugar, baking powder, salt, and sprinkles. Add melted butter and vanilla extract; mix with fork until small clusters form. Spread on a lined baking sheet and bake for 15 minutes, stirring halfway through. Cool completely.
05 - Using a stand mixer, beat butter, shortening, and cream cheese until smooth. Add vanilla extract and salt. Gradually beat in powdered sugar until fluffy. Add milk as needed to achieve spreadable consistency.
06 - Mix whole milk and vanilla extract in a small bowl. Using a 6-inch cake ring, cut two full circles and two half circles from the cooled cake sheet.
07 - Place a cake round inside a lined 6-inch cake ring set on a cake board. Brush with vanilla milk mixture. Spread 1/5 of frosting over cake, sprinkle 1/3 of crumbs, and repeat layering: half-circles to fill gaps, milk soak, frosting, and crumbs. Top with final cake round, soak, and finish with remaining frosting and crumbs or sprinkles.
08 - Chill assembled cake in ring for at least 1 hour, or up to overnight. Remove ring, transfer to serving platter, and serve at room temperature.
# Expert Tips:
01 -
- The vanilla milk soak makes every layer impossibly moist without being soggy
- That crunch from the birthday crumbs against the creamy frosting is absolutely addictive
02 -
- Room temperature ingredients are non negotiable here or your batter will separate
- The cake ring method looks intimidating but actually makes assembly way easier than free stacking
03 -
- Use a kitchen scale for the flour, too much and the cake turns dense and gummy
- Let the crumbs cool completely or they will steam and get sad instead of staying crunchy