Mix the crumbled shortbread biscuits, brown sugar and melted butter in a bowl, then distribute this mixture evenly on a muffin tray lined with paper liners and place in the freezer for 10-15 minutes.
While the bases are setting, beat the cream cheese with the sugar in a medium bowl until creamy, add the sour cream, eggs, vanilla sugar, lemon juice and lemon zest one after the other and stir well.
Distribute the cream cheese mixture evenly on the molds and bake in the preheated oven at 175 ° C (top / bottom heat) for about 20 minutes. Remove from oven and allow to cool.
Remove the cooled muffins from the mold and serve garnished with the berries and powdered sugar.
The muffins taste best if they were in the refrigerator before consumption, but that doesn`t have to be the case.