Happy Birthday Cake Slice

Featured in: Sweet Gatherings

This joyful dessert features a moist vanilla sponge cake layered with smooth buttercream frosting, then adorned with colorful sprinkles. The cake’s tender crumb is achieved by creaming butter and sugar before gently folding in flour and baking powder, ensuring a soft texture. The buttercream frosting combines softened butter, powdered sugar, milk, and vanilla extract for a rich finish. Once assembled, the treat is perfect for celebrating special occasions, offering a delightful combination of creamy, sweet, and festive flavors.

Updated on Thu, 04 Dec 2025 13:22:00 GMT
A slice of Happy Birthday Cake, layered with buttercream and sprinkles, ready to be enjoyed. Save
A slice of Happy Birthday Cake, layered with buttercream and sprinkles, ready to be enjoyed. | oventhyme.com

A festive, moist vanilla sponge cake layered with creamy buttercream and topped with colorful sprinkles—a joyful treat perfect for any celebration.

This cake quickly became a birthday favorite for our family because of its perfect balance of sweetness and texture.

Ingredients

  • For the Sponge Cake: 1 2/3 cups (210 g) all-purpose flour, 1 cup (200 g) granulated sugar, 1/2 cup (115 g) unsalted butter softened, 3 large eggs at room temperature, 1/2 cup (120 ml) whole milk, 2 tsp baking powder, 1/2 tsp salt, 1 tbsp pure vanilla extract
  • For the Buttercream Frosting: 1 cup (225 g) unsalted butter softened, 3 cups (360 g) powdered sugar sifted, 2 tbsp whole milk, 1 tsp pure vanilla extract, pinch of salt
  • For Decoration: 1/4 cup (40 g) colorful sprinkles

Instructions

Preheat Oven:
Preheat the oven to 350°F (175°C). Grease and line an 8-inch (20 cm) round cake pan with parchment paper.
Cream Butter and Sugar:
In a large bowl, cream together the butter and sugar until light and fluffy, about 3 minutes.
Add Eggs and Vanilla:
Beat in the eggs one at a time mixing well after each addition. Stir in the vanilla extract.
Mix Dry Ingredients:
In a separate bowl whisk together the flour baking powder and salt.
Combine Wet and Dry:
Add the dry ingredients to the wet mixture in three parts alternating with the milk beginning and ending with the flour. Mix until just combined.
Prepare Batter:
Pour the batter into the prepared cake pan and smooth the top.
Bake:
Bake for 28-32 minutes or until a toothpick inserted in the center comes out clean.
Cool Cake:
Let the cake cool in the pan for 10 minutes then turn out onto a wire rack to cool completely.
Make Frosting:
Beat the butter until creamy. Gradually add powdered sugar milk vanilla and salt beating until smooth and fluffy.
Assemble:
Once the cake is completely cool slice it horizontally to create two layers. Spread frosting between the layers and over the top and sides.
Decorate:
Decorate with colorful sprinkles. Slice and serve.
Imagine the sweetness! A beautifully decorated Happy Birthday Cake slice with fluffy white frosting, ready to eat. Save
Imagine the sweetness! A beautifully decorated Happy Birthday Cake slice with fluffy white frosting, ready to eat. | oventhyme.com

Celebrating birthdays with this cake has created wonderful memories full of smiles and joy.

Notes

Pairs well with sparkling wine or fresh lemonade.

Required Tools

8-inch (20 cm) round cake pan, electric mixer, mixing bowls, rubber spatula, wire rack, serrated knife

Allergen Information

Contains eggs milk wheat (gluten) and dairy. Check all packaged decorations for potential allergens.

Moist vanilla cake topped with creamy frosting and colorful sprinkles, this Happy Birthday Cake looks delicious. Save
Moist vanilla cake topped with creamy frosting and colorful sprinkles, this Happy Birthday Cake looks delicious. | oventhyme.com

This birthday cake is sure to bring smiles to your celebration and can be easily customized.

Kitchen Guide

What makes the sponge moist and tender?

The combination of creamed butter and sugar, along with eggs and milk, creates a tender, moist crumb by adding richness and moisture throughout the sponge.

How can I ensure the layers are even?

Allow the sponge to cool completely before slicing horizontally. Use a serrated knife for a clean, even cut and spread the frosting evenly between layers.

Can the decoration be customized?

Yes, colorful sprinkles can be swapped for nuts, fruit zest, or edible flowers to vary the presentation and flavor.

Is there a way to add fruit flavor to this dessert?

Adding a layer of fruit jam between the sponge layers enhances the flavor with a fresh, fruity note.

How to store the cake to keep it fresh?

Store the layered cake covered in an airtight container at room temperature for up to 2 days, or refrigerate for longer freshness.

Happy Birthday Cake Slice

Moist vanilla sponge layered with creamy buttercream and colorful sprinkles for festive moments.

Prep duration
25 min
Kitchen time
30 min
Complete duration
55 min
Created by Grace Mitchell


Skill level Medium

Heritage International

Output 8 Portions

Dietary requirements Meat-free

What you'll need

Sponge Cake

01 1 2/3 cups all-purpose flour
02 1 cup granulated sugar
03 1/2 cup unsalted butter, softened
04 3 large eggs, room temperature
05 1/2 cup whole milk
06 2 teaspoons baking powder
07 1/2 teaspoon salt
08 1 tablespoon pure vanilla extract

Buttercream Frosting

01 1 cup unsalted butter, softened
02 3 cups powdered sugar, sifted
03 2 tablespoons whole milk
04 1 teaspoon pure vanilla extract
05 Pinch of salt

Decoration

01 1/4 cup colorful sprinkles

Method

Phase 01

Prepare the Oven and Pan: Preheat the oven to 350°F. Grease and line an 8-inch round cake pan with parchment paper.

Phase 02

Cream Butter and Sugar: In a large bowl, cream the butter and granulated sugar until light and fluffy, approximately three minutes.

Phase 03

Incorporate Eggs and Vanilla: Beat in the eggs one at a time, mixing thoroughly after each addition. Stir in the vanilla extract.

Phase 04

Combine Dry Ingredients: Whisk together flour, baking powder, and salt in a separate bowl.

Phase 05

Mix Batter: Add dry ingredients to wet mixture in three portions, alternating with milk, beginning and ending with dry ingredients. Mix until just combined.

Phase 06

Bake the Sponge: Pour batter into the prepared pan and smooth the surface. Bake for 28 to 32 minutes or until a toothpick inserted into the center comes out clean.

Phase 07

Cool the Cake: Allow the cake to cool in the pan for ten minutes, then transfer to a wire rack and cool completely.

Phase 08

Prepare Buttercream: Beat butter until creamy; gradually add powdered sugar, milk, vanilla extract, and a pinch of salt, beating until smooth and fluffy.

Phase 09

Assemble Layers: Once cooled, slice the cake horizontally into two layers. Spread buttercream between layers, then cover top and sides.

Phase 10

Decorate and Serve: Top the cake with colorful sprinkles. Slice and serve.

Kitchen tools needed

  • 8-inch round cake pan
  • Electric mixer
  • Mixing bowls
  • Rubber spatula
  • Wire rack
  • Serrated knife

Allergy notes

Always review ingredients for potential allergens and seek professional medical advice when uncertain.
  • Contains eggs, milk, wheat (gluten), and dairy.
  • Check packaged decorations for allergens.

Nutrition breakdown (per portion)

Values shown are estimates only - consult healthcare providers for specific advice.
  • Energy: 430
  • Fats: 21 g
  • Carbohydrates: 57 g
  • Proteins: 4 g