Topping
Into a saucepan, add the butter and let it melt. Add 250ml of milk and the wheat flour, mix until a mixture is formed. Add another 250 ml of milk and stir until it thickens. Add salt and spices to taste, stir again.
Add another 250ml of milk and the table cream, mix well until it slightly thickens.
Set aside.
Roll out the pastry sheet, add the mozzarella and the ham slices on it, until you've used up all the cheese and ham. After that, roll this dough tight over the filling, pressing down on it.
Wrap the roll in plastic wrap - you can use the plastic wrap that came with the pastry sheet - and freeze for 30 minutes.
Take the roll out of the freezer and unwrap it, cut it into round slices, about 2cm-thick.
Transfer half of that sauce we've set aside to a baking dish, place the slices over this sauce, and cover them with the rest of the sauce. Top it with mozzarella cheese slices and bake in a preheated oven at 180°C (356°F) for 20 minutes.
Serve.