Galaxy Graduation Cake Stars (Printable)

A celestial cake with galaxy buttercream and edible star decorations, perfect for celebrations.

# 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 - Gel food coloring: black, navy blue, purple, pink, and teal

→ Decoration

14 - Edible gold and silver star sprinkles
15 - Edible glitter or luster dust
16 - White gel food coloring

# Directions:

01 - Preheat oven to 350°F. Grease and line three 8-inch round cake pans with parchment paper.
02 - In a large mixing bowl, cream together softened butter and granulated sugar until light and fluffy, approximately 3-4 minutes.
03 - Add eggs one at a time, beating well after each addition. Mix in vanilla extract until fully combined.
04 - In a separate bowl, whisk together flour, baking powder, and salt.
05 - Add dry ingredients to the wet mixture in three parts, alternating with milk, beginning and ending with flour. Mix until just combined.
06 - Divide batter evenly among the three prepared pans.
07 - Bake for 30-35 minutes or until a toothpick inserted in the center comes out clean.
08 - Cool cakes in pans for 10 minutes, then transfer to wire racks to cool completely.
09 - Beat softened butter until creamy. Gradually add sifted powdered sugar, then milk and vanilla extract. Beat until fluffy.
10 - 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.
11 - Place random spoonfuls of each colored buttercream onto a large piece of plastic wrap. Roll up to form a log. Snip one end and transfer to a piping bag fitted with a large round tip.
12 - Place first cake layer on a serving plate. Spread a thin layer of galaxy buttercream. Repeat with remaining layers.
13 - Apply a generous crumb coat of buttercream all over the cake. Chill for 20 minutes.
14 - Pipe and spread galaxy buttercream over the cake, swirling gently with an offset spatula to create a marbled galaxy effect.
15 - Use white gel food coloring with a food-safe paintbrush or splatter tool to flick on stars across the cake surface.
16 - Decorate with edible gold and silver star sprinkles and sprinkle edible glitter or luster dust. Optional: Add a graduation cap cake topper.

# Expert Tips:

01 -
  • It looks like you spent hours perfecting it, but the galaxy swirl technique is surprisingly forgiving and hides happy accidents beautifully.
  • You get to play with colors and create something genuinely unique—no two galaxy cakes look the same, which feels right for marking someone's one-of-a-kind moment.
02 -
  • Room temperature ingredients seem like a small detail until you've made this cake twice and learned the hard way that cold eggs and butter create a grainy, separated texture that no amount of beating fixes.
  • Sifting powdered sugar before measuring is not optional—I skipped it once and ended up with lumpy buttercream that no amount of love could smooth out, teaching me that little steps prevent big frustrations.
03 -
  • If your gel food coloring seems stubborn, let the buttercream sit for a minute after adding color and the hue will deepen beautifully—patience beats aggressive stirring.
  • Use an angled offset spatula rather than a straight one; it gives you better control when you're creating that galaxy swirl and adding those final details.
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