Grind the biscuits with the butter.
Cover a rectangular tray with stretch wrap. Distribute the biscuit mixture along the bottom and halfway up the walls, while pressing.
Beat the cottage cheese to a smooth consistency with a mixer or immersion blender.
Melt the white chocolate, mixed with 1 tbsp oil, on the stove and pour it into the cottage cheese. Stir well.
Grate the dark chocolate directly over the cottage cheese mixture and stir. Pour this mixture over the biscuit base and smooth it out.
Sprinkle the caramelized walnuts on top.
Leave in the fridge for at least 10-12 hours for the dessert to harden well.