Galaxy Graduation Cake Stars (Printable)

A stunning celestial cake with galaxy buttercream and edible stars, perfect for festive occasions.

# What You’ll Need:

→ Cake

01 - 2½ cups all-purpose flour
02 - 2 cups granulated sugar
03 - 1 cup whole milk, room temperature
04 - 1 cup unsalted butter, softened
05 - 4 large eggs, room temperature
06 - 2½ teaspoons baking powder
07 - ½ teaspoon salt
08 - 1 tablespoon vanilla extract

→ Galaxy Buttercream

09 - 1½ cups unsalted butter, softened
10 - 5 cups powdered sugar, sifted
11 - ¼ cup whole milk
12 - 2 teaspoons vanilla extract
13 - Black gel food coloring
14 - Navy blue gel food coloring
15 - Purple gel food coloring
16 - Pink gel food coloring
17 - Teal gel food coloring

→ Decoration

18 - Edible gold star sprinkles
19 - Edible silver star sprinkles
20 - Edible glitter or luster dust
21 - White gel food coloring

# How to Prepare:

01 - Preheat oven to 350°F. Grease and line three 8-inch round cake pans with parchment paper.
02 - In a large bowl, cream together butter and sugar until light and fluffy. Add eggs one at a time, beating well after each addition. Mix in vanilla extract.
03 - In a separate bowl, whisk together flour, baking powder, and salt.
04 - Add dry ingredients to wet mixture in three parts, alternating with milk, beginning and ending with flour. Mix until just combined.
05 - Divide batter evenly among prepared pans. Bake for 30 to 35 minutes until a toothpick inserted in center comes out clean.
06 - Cool cakes in pans for 10 minutes, then transfer to wire racks to cool completely.
07 - Beat softened butter until creamy. Gradually add powdered sugar, then milk and vanilla. Beat until fluffy.
08 - Divide buttercream into four or five bowls. Tint each with a different galaxy color using gel food coloring: black, navy blue, purple, pink, and teal.
09 - Place random spoonfuls of each color onto plastic wrap. Roll up to form a log. Snip one end and transfer to piping bag fitted with large round tip.
10 - Place one cake layer on serving plate. Spread thin layer of galaxy buttercream. Repeat with remaining layers.
11 - Apply generous crumb coat over entire cake. Chill for 20 minutes.
12 - Pipe and spread galaxy buttercream over cake, swirling gently with offset spatula to create marbled galaxy effect.
13 - Use white gel food coloring and food-safe paintbrush or splatter tool to flick stars across cake surface.
14 - Decorate with edible gold and silver star sprinkles and sprinkle edible glitter or luster dust over entire surface.
15 - Add graduation cap cake topper for festive touch.

# Expert Suggestions:

01 -
  • The galaxy buttercream technique looks like you spent hours on it but actually comes together in minutes with a clever plastic wrap trick.
  • Room temperature ingredients mean fewer lumps and a cake that rises evenly, so you'll actually get that gorgeous three-layer structure every time.
  • Gel food coloring creates those deep, jewel-toned hues that food coloring paste simply can't match, and the colors stay vivid even after a few days.
  • This cake celebrates someone without demanding you be a pastry chef—medium difficulty is honest, not intimidating.
02 -
  • Buttercream that looks slightly grainy or separated usually means your ingredients weren't at the same temperature—room temperature everything is non-negotiable for a smooth final product.
  • If your piped galaxy buttercream looks muddy instead of vibrant, your gel coloring wasn't dark enough; don't be afraid to add more color than you think you need.
  • The plastic wrap trick works because it keeps the colors distinct until the moment you start piping, so the buttercream doesn't blend into brown before it hits the cake.
03 -
  • If you don't have three cake pans, bake in batches using the same pans cooled between rounds—just add five minutes to your baking time for each subsequent batch since the pans will be slightly warmer.
  • The plastic wrap buttercream roll can be made a day ahead and stored in the refrigerator, so you can do the hardest part of the decoration whenever you have time.
  • For a less structured galaxy, forget the piping bag entirely and use an offset spatula to randomly spread blobs of different colors directly onto the cake, then swirl with another spatula—it's more forgiving and looks equally impressive.
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