Peel and chop the onion. Then knead it with minced meat, egg, tomato paste and breadcrumbs with the dough hooks of the hand mixer. Season everything with salt and pepper. Form from the minced mass with wet hands about 12 balls. Cook about 2 l water with 1 teaspoon salt in a big cooking pot.
Heat oil in a coated pan and fry the meatballs in it for about 5 minutes. Add the noodles to the boiling salted water and cook them for about 8 minutes (but also check the package), stirring once
Pour the pizza tomatoes and 1/8 l water over the meatballs and add the peas and carrots unfrozen. Boil everything up and let it simmer open for about 5 minutes. Stir the sauce from time to time. Pour the noodles into a sieve and let them drain well
Drain the mozzarella. Cut it in half and slice it. Divide the pasta into four plates. Season the sauce with salt and pepper and put it on the noodles. Put the mozzarella slices on top, let them melt and garnish everything with oregano