Divide half of the chopped cantuccini between six dessert glasses. Cook the pudding powder with sugar, milk and whipped cream according to the instructions on the packet to make a pudding. Remove from heat and stir in the egg liqueur. Divide the pudding evenly between the glasses. Spread the rest of the cantuccini on top.
Mix the mascarpone and yoghurt and stir in the powdered sugar and cream stiffener. Spread the cream on the glasses and chill for about 1 hour. Wash the strawberries and puree them with the sugar.
Before serving, distribute the strawberry puree between the glasses.