In salted water, boil spaghetti to the state of al dente according to the package instructions. Drain, add 1 egg and parmesan to spaghetti and mix thoroughly.
Heat olive oil over medium heat. Put chopped onion in butter and cook for about 5 minutes until it softens. Add the chopped garlic and mix the vegetables. Put the minced meat and fry it for about 6 minutes.
Then add tomato paste to the filling, mix, and a minute later add the grated tomatoes, oregano, salt and pepper. Cook over low heat for another 10 minutes. In a separate bowl, mix the ricotta and the remaining egg.
Put a little meat filling on the bottom of the baking dish. Top with half the spaghetti, half the filling, half the ricotta and half the mozzarella. Repeat the layers again and place the lasagna in a preheated 180 ° C oven for 25 minutes. Sprinkle with chopped parsley before serving.
