• Gently melt the butter in a saucepan. Add the crushed biscuits and mix until the butter has been absorbed.
• Remove from the heat and, while still warm, press the mixture (using the back of a spoon) into the bottom of a lined 23cm/9inch springform or flan tin. Leave to set for one hour in the fridge.
• While it is chilling, grate the chocolate. Set aside in the fridge if your kitchen is warm.
• In a bowl, whip the cream until it forms soft peaks.
• In a separate bowl, beat the cream cheese until it is soft. Beat in the icing sugar and a shot of Baileys. Fold in the whipped cream and three-quarters of the chocolate. When the mixture is smooth, smooth it evenly onto the biscuit base.
• Refridgerate and allow to set for at least two hours. If you can bear to leave it overnight, so much the better.

To serve:

• Remove from the tin and decorate. You can either sprinkle the remaining grated chocolate over the top for a simple finish, or add some individual maltesers and flakes for a more elegant and ceremonial dressing.