Drain the pineapple pieces and collect the juice. Mix the mascarpone and quark with the pineapple juice until smooth, stir in the sugar, whip the cream until stiff and fold into the mascarpone quark cream.
Fill 6 dessert bowls with a little mascarpone and quark cream, spread the amaretti over them. Drizzle half of the egg liqueur over the amarettini, then add the pineapple pieces. Spread the rest of the mascarpone cream on top and drizzle everything with the remaining egg liqueur.
Melt the butter in a pan, toast the almond flakes in it and then sprinkle on the desserts. To finish off each dessert, add an amarettini.
Chill until serving, can also be prepared the day before.