Place over medium-high heat.

Pour the oil into the pot, wait a couple of seconds until it is hot, and immediately add the finely chopped onion and the crushed garlic.

When the onion is translucent, add the ground beef, oregano, pepper, and salt.

Cook for a few minutes until the meat loses its pink color.

Add the marinara sauce, reduce the heat to medium-low heat, place a lid and cook covered for about ten minutes. Turn off and reserve.

In a large pot, bring about two to three liters of water to a boil.

When it starts to bubble add a teaspoon of salt.

And then add the shell pasta, cook for about five or six minutes, don't worry if your pasta is still a bit raw. The pasta will finish cooking in the oven. Remove from heat and strain.

While the pasta is cooking, mix the Parmesan cheese, the cream, and two cups of mozzarella cheese in a bowl (keep one cup for the topping). Stir until you get a compact cream.

Preheat the oven to 160 ° / 320 ° F.

Spread a little oil on an ovenproof tray.

Place a layer of meat on the tray, be sure to cover the entire surface of the tray.

Take the pasta filling, and one by one fill pasta shells with the mixture cheese. You can do it with a teaspoon or directly with your hands.

Arrange the filled pasta neatly on the tray, then top with the remaining meat sauce.

Top with mozzarella topping and cook for about 20 minutes.