Beat the cream with 1 teaspoon sugar until stiff. Mix the remaining sugar with cocoa powder and 5 tablespoon cold milk. Bring the remaining milk to the boil and stir in the cocoa. Mix cocoa with coffee and 3 tablespoons of peppermint syrup. Pour into 2 cups and add a dollop of cream to each.
Halve the after-eight tablets diagonally and stick them in the cream. Drizzle the rest of the peppermint syrup over the cream and decorate with mint leaves.