Whip the yolks with the sugar and mineral water over a bain-marie until creamy. Soak the gelatine in cold water, squeeze it out and let it melt in the whipped amount. Remove the mixture from the water bath. Continue beating until lukewarm. Add the mascarpone and mix with the juice of one lemon until smooth. Stir in the pineapple cubes and the mint cut into strips. Whip the egg whites with the vanilla sugar until stiff and fold into the mascarpone together with the whipped cream.
Spread out a sheet of cling film. Mix the cocoa powder with the milk and season with chocolate liqueur.
Spread a little bit of the pineapple cream in the mold as the first layer.
Soak the sponge cake in the cocoa milk and put a layer on top of the cream. Repeat this process until the mold is full.
Cover with plastic wrap and set aside to cool. When the crem is firm, turn it out of the mold and cut it into slices. Arrange these on a plate and garnish with fruit sauces and fresh mint.
Biscuits: Whip the yolks and confectioners’ sugar until creamy. Add the vanilla pulp and lemon zest and beat until smooth. Beat the egg whites and granulated sugar until stiff. Gradually add the sugar. Add the two masses together. Sift the flour into the mixture and gently fold in. Pour into a piping bag with a nozzle and pipe into a baking sheet lined with parchment paper.