In a large bowl beat the two kinds of sugar and the melted butter with a hand whisk, until well combined. It is ok if few crumbs of the dark brown sugar to remain. Add egg and vanilla and whisk until smooth. Gradually add flour, cocoa powder, duding powder and baking powder, folding them gently with the wooden spoon until a soft dough is formed. At the end add the white chocolate pieces and mix carefully with the wooden spoon until evenly distributed in the dough.
Cover the bowl with a cling film and let the dough rest in the fridge for 30-60 minutes (if the dough is refrigerated longer, take it out of the fridge 10 minutes before starting to shape the cookies).
When the dough is refrigerated and the cream cheese fillings are frozen, start taking pieces out of the dough. Extend them in your hand and make a shape like a well. Place inside the cavity one of the frozen fillings and cover it with another piece of dough. Make a bowl and place it in a baking tin covered with parchment paper.
Continue the same process until using all the dough and frozen fillings. When the first tin is full, place it in the fridge for 10 minutes before baking. Make sure the cookies are arranged not too close one next to another because they will grow.
Bake for 10-15 minutes or until the edges start hardening slightly but the tops are still soft.
Let them cool for 10-15 minutes before serving.
Store in airtight container in the fridge for about a week.