# Components:
→ Vanilla Sponge
01 - 2½ cups all-purpose flour
02 - 2½ teaspoons baking powder
03 - ½ teaspoon salt
04 - 1 cup unsalted butter, room temperature
05 - 2 cups granulated sugar
06 - 4 large eggs, room temperature
07 - 1 tablespoon pure vanilla extract
08 - 1 cup whole milk, room temperature
→ Galaxy Buttercream
09 - 1½ cups unsalted butter, room temperature
10 - 5 cups powdered sugar, sifted
11 - ¼ cup whole milk
12 - 2 teaspoons vanilla extract
13 - Gel food coloring: navy blue, purple, black, and teal
14 - Edible glitter in silver, blue, or iridescent finish
→ Decoration
15 - White fondant, optional for zodiac symbols or stars
16 - Silver star sprinkles, optional
# Directions:
01 - Preheat oven to 350°F. Grease and line three 8-inch round cake pans with parchment paper.
02 - In a medium mixing bowl, whisk together flour, baking powder, and salt until evenly distributed.
03 - In a large mixing bowl, cream butter and sugar together until light and fluffy, approximately 3 to 4 minutes.
04 - Add eggs one at a time, beating well after each addition. Mix in vanilla extract until fully combined.
05 - Alternately add the flour mixture and milk to the butter mixture, beginning and ending with flour. Mix until just combined to avoid overdeveloping gluten.
06 - Divide batter evenly among the three prepared pans.
07 - Bake for 25 to 30 minutes, or until a toothpick inserted into the center comes out clean.
08 - Allow cakes to cool in pans for 10 minutes, then turn out onto a wire rack to cool completely.
09 - Beat butter until creamy. Gradually add powdered sugar, milk, and vanilla; beat until smooth and fluffy.
10 - Divide buttercream into four separate bowls. Tint each bowl with distinct galaxy colors: navy blue, purple, teal, and black.
11 - Place alternating spoonfuls of each colored buttercream onto the cake layers and sides. Use an offset spatula to create gentle swirls for a celestial galaxy effect.
12 - Sprinkle edible glitter generously over the cake. Add fondant zodiac symbols or stars if desired.
13 - Refrigerate for 30 minutes before slicing to allow the buttercream and glitter to set properly.