Mix the margarine, egg yolks and sugar until frothy. Add the nuts, rum and chocolate shavings. Mix in flour and baking powder and stir in. Beat egg whites into snow and fold in carefully.
Line a baking sheet with parchment paper. Spread the dough evenly on top and top with sweet or sour cherries. Bake in the preheated oven at 175 ° C top / bottom heat for approx. 50 minutes.