Ingredients:

  • 150g (about 5 oz) digestive biscuits (or graham crackers)
  • 75g (about 2.5 oz) unsalted butter, melted
  • 50g (about ¼ cup) granulated sugar (optional)
  • 200g (about 7 oz) dark chocolate (70% cocoa), chopped
  • 3 large eggs, separated
  • 50g (about ¼ cup) granulated sugar
  • 1 teaspoon vanilla extract
  • 300ml (about 1 ¼ cups) heavy cream
  • 1 tablespoon brewed espresso or strong coffee (optional)

Instructions:

  1. Preheat the oven to 180°C (350°F). Crush the digestive biscuits in a food processor until fine. In a bowl, combine the crushed biscuits, melted butter, and sugar until crumbly. Press the mixture into the bottom and sides of the pie dish evenly. Bake for 10 minutes or until slightly golden. Allow to cool completely.
  2. Melt the chopped chocolate in a heatproof bowl over simmering water or in the microwave until smooth. Let it cool slightly. In a separate bowl, whisk the egg yolks with granulated sugar and vanilla until pale and frothy. Add the melted chocolate to the egg yolk mixture and mix until well combined.
  3. In another clean bowl, whip the heavy cream until soft peaks form. In a separate bowl, whisk the egg whites until soft peaks form. Carefully fold the whipped cream into the chocolate mixture, then gently fold in the egg whites until no streaks remain.
  4. Pour the mousse filling into the cooled crust, smoothing the top with a spatula. Cover and refrigerate for at least 4 hours or until set.
  5. Once set, slice the pie and serve with whipped cream or chocolate shavings on top.