Start by cutting the onions into thin strips and transfer them to a baking tin, spread them and add a drizzle of olive oil. Set aside.
In a bowl, add the ground beef, season it with the salt, the black pepper, the sweet paprika, the dried parsley, the crushed garlic cloves, and the nutmeg, mix very well until incorporated.
Get a portion of this meat and shape it into a ball then into a burger patty. I managed to make 6 patties.
Transfer the burgers to the baking tin with the onions.
Top the patties with the grated boiled eggs.
Grate the potatoes and top all the egg burgers with them.
Now, top the burgers with 50g of grated mozzarella cheese.
Add mayonnaise, to taste.
Take to a preheated oven at 180°C (350°F) and bake for 30 minutes.
Serve.