Wash and stone the cherries. Roughly chop the chocolate. Separate eggs. Beat egg whites and 1 pinch of salt until stiff. Cream 400 g butter, sugar and egg yolk in a second bowl with the whisks of the mixer.
Stir in rum, cinnamon, almonds and chocolate. Mix baking powder and flour, sieve onto the mixture and stir in. Fold in the beaten egg white.
Smooth the dough on the greased fat pan (32 x 39 cm) sprinkled with breadcrumbs. Spread cherries on top. Bake in the hot oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer) for approx. 40 minutes.
Let it cool down. Dust with icing sugar. Serve with whipped cream.