Preheat oven to 180 C / Gas 4. Grease and flour three 20cm round cake tins.
Prepare cake mix according to package directions. Pour batter into the prepared tins.
Bake in preheated oven for 30 minutes. Let cake cool slightly then pierce cakes with a fork. Pour the coffee liqueur gradually over the three cake layers.
Prepare the chocolate mousse according to the package directions. Let chill in the refrigerator.
Once cake is cool break it into pieces. Layer cake pieces, chocolate mousse, Daim bars and whipped cream, 1/3 at a time in a large glass bowl. Grate the milk chocolate over the top. Let chill in refrigerator for several hours before serving.
Chocolate mousse mix
Can be purchased online if you can't find it in your local supermarket.