Ingredients:

  • 1/2 cup (115g) unsalted butter, melted
  • 3/4 cup (150g) granulated sugar
  • 2 large eggs
  • 1 tsp (5ml) vanilla extract
  • 1 cup (125g) all-purpose flour
  • 1/3 cup (30g) Dutch-processed cocoa powder
  • 1/2 tsp (2g) baking soda
  • 1/2 cup (120ml) buttermilk
  • 6 oz (170g) dark chocolate (60% cocoa), chopped
  • 4 1/2 cups (1080ml) heavy whipping cream, divided
  • 3 tbsp (45g) powdered sugar
  • 2 tsp (10g) gelatin powder
  • 6 oz (170g) milk chocolate, chopped
  • 6 oz (170g) white chocolate, chopped
  • 1 tsp (5ml) lemon juice
  • 1/2 cup (120ml) water
  • 1/2 cup (120g) granulated sugar
  • 1/2 cup (120ml) condensed milk
  • 4 oz (115g) white chocolate, finely chopped
  • 1 tbsp (15ml) neutral oil

Instructions:

  1. Preheat oven to 350°F (175°C) and grease a 9-inch springform pan.
  2. Mix melted butter and sugar, then beat in eggs and vanilla.
  3. Sift in flour, cocoa, and baking soda, alternating with buttermilk; stir until combined.
  4. Pour batter into the pan and bake for approximately 25 minutes or until a toothpick inserted in the center comes out clean. Let cool completely in the pan.
  5. Prepare the Dark Chocolate Mousse: Heat 1/2 cup heavy cream until simmering, pour over 170g dark chocolate, let sit for 2 minutes, and stir until glossy.
  6. Whip 1 cup heavy cream with 2 tbsp powdered sugar to soft peaks, then fold into the dark chocolate mixture. Pour over the cooled sponge and chill.
  7. Prepare the Milk Chocolate Mousse: Repeat the process using 170g milk chocolate, 1.5 cups heavy cream (divided), and 1 tbsp powdered sugar. Pour over the dark layer and chill.
  8. Prepare the White Chocolate Mousse: Repeat the process using 170g white chocolate, 1.5 cups heavy cream (divided), and 1 tsp lemon juice. Pour over the milk layer and freeze.
  9. Prepare the Mirror Glaze: Heat water and 120g sugar. Stir in gelatin and condensed milk. Pour over 115g white chocolate and neutral oil, stirring until smooth.
  10. Pour the mirror glaze over the frozen cake to create a reflective finish and refrigerate until set.