Ingredients:

  • 2 cups (250g) all-purpose flour
  • 2 cups (400g) granulated sugar
  • ¾ cup (75g) unsweetened cocoa powder
  • 2 tsp (10g) baking soda
  • 1 tsp (5g) baking powder
  • 1 tsp (5g) salt
  • 1 cup (240ml) buttermilk, room temperature
  • ½ cup (120ml) vegetable oil
  • 2 large eggs, room temperature
  • 2 tsp (10ml) vanilla extract
  • 1 cup (240ml) boiling water
  • 1 ½ cups (340g) unsalted butter, softened
  • 5 cups (600g) powdered sugar
  • 2 tbsp (30ml) heavy cream
  • 1 tsp (5ml) peppermint extract
  • 1 cup (170g) Andes mint chocolate chips, finely chopped
  • 1 drop green food coloring

Instructions:

  1. Preheat your oven to 350°F (175°C) and grease two 9-inch round cake pans.
  2. Whisk together the flour, sugar, cocoa, baking soda, baking powder, and salt in a large bowl until no lumps remain.
  3. Stir in the buttermilk, oil, eggs, and vanilla. Mix until smooth.
  4. Carefully pour in the boiling water and stir until incorporated; the batter will be very thin.
  5. Divide the batter evenly between the two pans and bake for 30–35 minutes, or until a toothpick inserted into the center comes out with just a few moist crumbs.
  6. Cool cakes in the pans for 10 minutes before transferring to a wire rack to cool completely.
  7. Beat the softened butter until creamy (about 3 minutes).
  8. Gradually add powdered sugar and heavy cream, beating on low then high until fluffy.
  9. Fold in the peppermint extract, chopped Andes mint chips, and optional green food coloring.
  10. Frost the cooled cake layers and chill for 2 hours to ensure frosting stability before serving.