Preheat the oven to 190 °C for the Toffifee Hazelnut Muffins. Grease the muffin tray well or place paper baking cups in the cups.
Mix flour, baking powder and hazelnuts in a bowl. Melt cooking chocolate over steam. In a second bowl, beat butter, sugar, vanilla sugar, cooking chocolate and gradually eggs until fluffy.
Add flour mixture and beat until blended. Fill ramekins halfway with batter, place one Toffifee on each, cover with remaining batter and bake for about 20-25 minutes. Remove the Toffifee Hazelnut Muffins and let them cool.