Mix flour and baking powder. Whisk the egg. Stir in sugar, vanilla sugar, butter and buttermilk. Carefully fold in the flour mixture. Coarsely chop 7 biscuits and fold into the dough
Grease the recesses of the muffin tray (12 recesses). Place 1 biscuit in each trough. Spread the dough in the troughs. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for about 25 minutes. Let muffins rest for about 5 minutes. Carefully remove from the tray. Let them cool down. Coarsely chop 3 biscuits. Decorate muffins with 1 tsp. sour cream and chopped biscuits
Waiting time approx. 1 hour