Ingredients:

  • 2 cups (250g) all-purpose flour, plus more for dusting
  • ¾ cup (75g) unsweetened cocoa powder
  • 1 ½ teaspoons baking powder
  • 1 ½ teaspoons baking soda
  • 1 teaspoon salt
  • 1 cup (200g) granulated sugar
  • ½ cup (100g) packed brown sugar
  • ½ cup (120ml) vegetable oil
  • 1 cup (240ml) buttermilk
  • 2 large eggs
  • 2 teaspoons vanilla extract
  • 1 cup (240ml) boiling water
  • 2 tablespoons brewed coffee
  • 12 ounces (340g) bittersweet chocolate, finely chopped
  • 1 cup (240ml) heavy cream
  • 1 cup (2 sticks) (226g) unsalted butter, softened
  • 4 cups (480g) powdered sugar
  • ¼ cup (60ml) heavy cream
  • 1 teaspoon vanilla extract
  • Gel food coloring: blue, purple, pink, black
  • Edible silver or gold glitter

Instructions:

  1. Prepare the Cake Pans: Grease and flour cake pans; line the bottom with parchment paper.
  2. Make the Cake Batter: Whisk dry ingredients. Cream together wet ingredients and sugars. Gradually add dry ingredients to wet ingredients. Stir in boiling water and coffee.
  3. Bake the Cakes: Divide batter evenly between pans. Bake until a toothpick inserted in the center comes out clean.
  4. Cool the Cakes: Let cool in pans for 10 minutes, then invert onto a wire rack to cool completely.
  5. Make the Chocolate Ganache: Heat heavy cream in a saucepan. Pour over chopped chocolate and let sit for a minute. Whisk until smooth and glossy.
  6. Make the Galaxy Buttercream: Beat butter until light and fluffy. Gradually add powdered sugar, then heavy cream and vanilla. Divide buttercream into several bowls and tint with different gel food colorings (blue, purple, pink, black).
  7. Assemble the Cake: Level cake layers if needed. Place one cake layer on a serving plate or cake stand. Spread with a layer of chocolate ganache. Top with the second cake layer.
  8. Frost the Cake: Crumb coat the entire cake with a thin layer of white buttercream. Chill for 30 minutes. Frost the cake with the tinted buttercream, creating a swirling 'galaxy' effect.
  9. Decorate: Pipe stars and other celestial shapes with different colored buttercreams. Sprinkle with edible glitter.
  10. Chill: Chill the cake for at least 30 minutes to allow the buttercream to set.