Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Place paper cups in the troughs of a muffin tray (12 troughs).
For the dough, break chocolate into pieces. Melt in a hot water bath. Mix eggs, sugar and 1 pinch of salt with a whisk. Stir in flour briefly. Lift the chocolate out of the water bath. Add butter in pieces and melt while stirring.
Stir chocolate butter into the egg mixture. Spread into the moulds. Bake in a hot oven for 12-15 minutes. Remove and let cool.
Whip cream until stiff for serving. Sort the berries, wash if necessary. Pass half the berries through a sieve and fold into the cream. Remove paper cups from the muffins. Spread the cream loosely over the muffins.
Decorate with remaining berries.