Wash the berries, sort them out and spread them on kitchen paper to dry. Cut the buns open horizontally. Brush cut surfaces with butter. Roast the bread roll halves in a large pan while turning them golden brown, take them out.
Sprinkle with cinnamon. Whip cream until stiff and mix with yoghurt. Grate 30 g marzipan finely and fold into the yoghurt cream with vanillin sugar. Spread the marzipan yoghurt on the cut surfaces of the milk rolls.
Cover with berries. Rub the rest of the marzipan over it. Decorate with mint.