Start by grating the potatoes and set them aside into a bowl filled with cold water.
Into another bowl, add the ground beef, the egg, the black pepper, the salt and the breadcrumbs, mix all the ingredients very well. After that, set aside.
Into another bowl, add the grated mozzarella cheese, the tomato chopped into small dices, the grated boiled eggs, the table cream, mix well.
After that, cover the bottom of a large baking dish with the grated potatoes, without the water, and spread well.
Cover the potatoes with thin onion strips.
Now cover a mason jar lid with a piece of plastic film and add 2 tablespoons of the meat into this lid. Wrap the meat in the plastic, shaped like the lid.
Transfer the shaped pieces of meat to the baking dish with the potatoes and onions.
Repeat this process with all the meat.
Then place a portion of the egg-cheese mixture on top of each piece of meat.
Take to a preheated oven at 180°C (356°F) and bake for 45 minutes. Baking time may vary depending on the power of your oven.
Serve.