Sautee the diced onions (if using), add in the meat and some water. Cook the beef well, until the water evaporates.

Grate the mozzarella

Add the tomato sauce to the beef, add in salt and pepper and parsley or basilic, if using.

Pour in some bechamel sauce into the pan, lay a layer of sheets

Add 1/3 of meat, then cover with the mozzarella

Lay another layer of the sheets and continue adding the filling in the same order, 3-4 layers in total

On the last layer of the sheets, pour some mozzarella, then add parmesan

Cover with foil and put to the 180° heated oven for 30 minutes. Take out the foil after 20 minutes.