Beat the Cremefine until stiff. Mix Qimiq vanilla with 50 g powdered sugar and the rum until smooth. Stir in the Cremefine well.
Puree blueberries with 100 g powdered sugar and the juice of the lemon. Break the biscuits into small pieces. In a dessert glass, place a few pieces of sponge cake, top with some of the blueberry puree and then a layer of cream.
Repeat until all 4 glasses are evenly filled.