Crumble the coffee biscuits with a rolling pin. Melt the butter and mix with the biscuit crumbs. Place egg yolks, eggs and sugar in a saucepan and stir until creamy over hot water until the sugar has dissolved. Stir in the espresso and 4 tablespoons of coffee liqueur and allow to cool.
Whip the cream until stiff and fold in the egg custard. Mix in the remaining liqueur to the biscuit crumbs. Grease the pan and line with foil. Place approximately 1/3 of parfait mixture into the pan. Spread half the cookie crumbs on it, then spread 1/3 of the parfait mixture on it, finally add the rest of the biscuit crumbs on top and smooth the top. Cover with foil for about 5 hours, place in the freezer and allow to freeze.
About 30 minutes before serving, place in the refrigerator. Then take it out of the pan, remove the foil and serve with coffee biscuits.