Firstly, from the 2 packs of sandwich cookies, remove the filling of the biscuit-sandwiches. Then in a grinding processor, grind the biscuit and add the melted butter. Form a cake base in a round pan with mechanism no. 26. In a deep bowl, whisk together the sandwich cookies, then add the sour cream, mascarpone cheese, powdered sugar, vanilla extract and mash until you get a thick, firm filling. Add the melted and already cooled white chocolate. Stir well and crush the remaining two boxes of sandwich cookies in the mixture. Stir the whole mixture well and pour it on the base in the pan. Leave it to harden for about 3-4 hours in the refrigerator and finally decorate it with whipped cream, a few sandwich cookies and colorful crumbs to decorate cakes.