Icecream leave briefly to relax. Strong coffee mix with liqueur and rum. In tray arrange half of the biscuits, which have previously soaked in a mixture of coffee and liqueur. With cooking spray half of the already wavy shape relax ice cream on biscuits. Then, in the same way on top of the other half initiate pre-soaked biscuits, on which is formed and the rest of the ice cream. Place in the freezer to harden and then sprinkle with cocoa. Optional can decorate with large chocolate chips.