1 cup heavy cream, whipped until it forms stiff peaks
1 Heath bar, chopped
A large high sided glass serving bowl
Preheat the oven to 350F. Grease and line with parchment a 9x12x2 sheet pan.
Prepare the sponge by beating the sugar and butter until creamy and lemon coloured, about three minutes. Add the eggs and beat until combined. Fold in the flour and cocoa and spoon into the prepared pan. Bake for about 15 minutes until the sponge springs back when pressed. Remove from the oven to a cooling rack to cool. Cut the sponge in half and freeze one half. Cut the remaining half into 1 inch chunks and place on the bottom of a large serving bowl.
Prepare the mousse by putting the sugar and water into a small heavy based pan over high heat. Do not stir, swirl the pan as the sugar starts to brown. Cook to a dark caramel and remove from the heat. Add the butter and cream and then the chocolate and whisk until smooth. Beat in the egg yolks and remove to a large bowl. Whip the egg whites until stiff fold into the chocolate mix. Allow the chocolate mixture to cool.
Pour the Baileys Irish cream over the sponge. Drain and dice the pears into bite size pieces and lay on top of the sponge. Pour the chocolate caramel mousse over the pears and refrigerate for at least two hours. This will help the mousse to set up and become a bit firmer.
Spread the cup of whipped cream over the mousse and sprinkle the chopped Heath bar over the top just before serving.