Ingredients:

  • 2 Large Eggs
  • 1/2 cup Granulated Sugar (for sponge)
  • 1/2 cup All-Purpose Flour (sifted)
  • 1/2 tsp Baking Powder
  • 1 tsp Orange Zest (finely grated)
  • 2 Tbsp Unsalted Butter (melted and cooled)
  • 1/4 cup Water (for syrup)
  • 2 Tbsp Granulated Sugar (for syrup)
  • 4 Tbsp Orange Curacao Liqueur (for syrup)
  • 2 packets Unflavored Gelatin Powder (about 4.5 tsp)
  • 1/2 cup Cold Water (for blooming gelatin)
  • 4 Large Egg Yolks
  • 1/2 cup Granulated Sugar (for mousse base)
  • 1/2 cup Fresh Orange Juice
  • 1/4 cup Orange Curacao Liqueur (for mousse)
  • 2 cups Heavy Whipping Cream (chilled)
  • 1 tsp Vanilla Extract

Instructions:

  1. Preheat oven to 350°F (175°C). Line the bottom of an 8-inch springform pan with parchment paper. Whisk eggs and 1/2 cup sugar until pale, thick, and tripled in volume (the ribbon stage, about 5-7 minutes). Gently fold the sifted flour, baking powder, and orange zest into the egg mixture. Fold in the cooled melted butter until just combined. Pour batter into the prepared pan and bake for 20-25 minutes, or until a skewer comes out clean. Cool completely on a wire rack, then return the sponge base to the cleaned springform ring.
  2. Combine 1/4 cup water and 2 Tbsp sugar in a small saucepan. Bring to a simmer, stirring until the sugar dissolves. Remove from heat, stir in 4 Tbsp Orange Curacao liqueur, and allow to cool slightly. Generously brush the entire surface of the cooled sponge base with the Curacao syrup.
  3. Sprinkle the gelatin powder over 1/2 cup cold water in a small bowl; let stand for 5-10 minutes until bloomed. Whisk egg yolks and 1/2 cup sugar together until pale. In a separate pan, gently warm the orange juice (do not boil). Gradually whisk the warm orange juice into the yolk mixture to temper the eggs. Return this tempered mixture to the saucepan and cook over low heat, stirring constantly, until the mixture thickens slightly and coats the back of a spoon (about 170°F/77°C). Do not boil.
  4. Remove the custard from heat. Add the bloomed gelatin mixture and whisk until completely dissolved and smooth. Strain the custard base through a fine-mesh sieve into a clean bowl. Stir in 1/4 cup Orange Curacao liqueur and vanilla extract. Let the mixture cool to room temperature (it should be slightly thicker but not fully set).
  5. In a chilled bowl, whip the heavy cream until stiff peaks form. Gently fold one third of the whipped cream into the cooled Curacao base to lighten it. Fold in the remaining cream in two additions, taking care not to deflate the mixture. Pour the mousse evenly over the soaked sponge base in the springform pan.
  6. Cover the cake loosely and refrigerate for a minimum of 4 hours, or ideally overnight, until the mousse is completely firm. Carefully run a thin, hot knife around the edge before releasing the springform ring. Garnish with fresh orange slices or candied orange peel before serving.