Peel and finely dice the onion and garlic. Wash, clean and halve the mushrooms. Heat oil in a pan. Sauté onions, garlic and mushrooms in it. Stir in tomato paste and add tomatoes.
Add herbs and bring to the boil. Season to taste with salt, pepper, sugar and paprika. Let simmer for about 3 minutes. Cook tortelloni in boiling salted water for about 1 minute and drain. In the meantime wash, clean, quarter, seed and dice the tomato.
Sprinkle tortelloni and sauce with diced tomatoes and serve garnished with oregano.