Let the puff pastry thaw. Roughly pluck the marzipan mixture. Mix the milk, marzipan and powdered sugar until creamy. Crumble the egg biscuits and fold into the marzipan mixture with 4 tablespoons of nut brittle.
Place the puff pastry sheets in two stacks on top of each other and roll them out into a rectangle (40 x 40 cm). Cut both rectangles into 4 squares. Peel the pears, core them with the core cutter and rub with lemon juice. Pour the marzipan mixture into the pears. Mix the egg yolks with the cream and brush half of the puff pastry.
Place the pears on the brushed side of the dough, fold the corners over and twist together at the top. Brush the outside of the dough with the remaining egg yolk and place the pears on baking paper sprinkled with the remaining brittle. Bake in the preheated oven on the second rack from the bottom at 200 ° C (convection 180 ° C) for 25-30 minutes.