• 1/3 cup (15g) good-quality instant coffee granules, dissolved in 1/4 cup (60ml) hot water
  • 150g good-quality dark chocolate, roughly chopped, plus grated chocolate to serve
  • 150g unsalted butter
  • 4 eggs, separated
  • 2 1/2 tablespoons Irish whiskey
  • 1/2 teaspoon vanilla extract
  • 150g caster sugar, plus extra 1 tablespoon
  • 300ml thickened cream
  • 2 tablespoons Baileys Irish Cream liqueur
  • Step 1 Place coffee, chocolate and butter in a heatproof bowl set over a pan of gently simmering water (don’t let the bowl touch the water), stirring until the chocolate and butter have melted. Remove bowl from heat and set aside.
  • Step 2 Place yolks, whiskey, vanilla, 150g sugar and 1 tablespoon cold water in a separate heatproof bowl set over the simmering water (don’t let the bowl touch the water) and whisk with electric beaters for 3 minutes or until thick and pale. Remove the bowl from the pan and sit in a larger bowl filled with iced water (don’t let any water get in the yolk mixture), then continue to whisk for a further 2-3 minutes until the mixture thickens and cools slightly. Stir in the chocolate mixture until combined.
  • Step 3 Whisk the eggwhites in a clean bowl with a pinch of salt until soft peaks form. Add the extra 1 tablespoon sugar and beat until stiff and glossy.
  • Step 4 Gently stir one-quarter of the eggwhite into the chocolate mixture to loosen, then fold in the remaining eggwhite until combined.
  • Step 5 Spoon the chocolate mousse into small serving glasses, leaving a 2cm gap at the top. Chill for 3-4 hours to set.
  • Step 6 Whisk thickened cream and Baileys together until stiff peaks form, then spoon over the mousse. Scatter with grated chocolate and serve chilled.