Peel and finely dice the onion and garlic. Heat 1 tablespoon of oil in a saucepan. Sauté onion and garlic in it. Add the tomatoes and juice, bring to the boil, cover and simmer at medium heat for 20-30 minutes, chopping the tomatoes slightly.
Season with vinegar, salt, pepper and approx. 1⁄2 TL sugar.
Meanwhile cook the pasta in 3-4 l boiling salted water (approx. 1 teaspoon salt per litre) according to the instructions on the packet. Preheat the oven grill (electric oven: 250 °C/circulating air: not suitable/gas. see manufacturer).
Finely crumble the chilli. Mix ricotta, 3 tablespoons of oil, oregano and chili. Season to taste with salt and pepper. Spread into a small ovenproof dish about 2 cm high. Gratinate under the hot grill for 4-7 minutes.
Grate parmesan. Clean, wash and shake dry the arugula. Season tomato sauce again. Drain the pasta and put it back into the pot. Add sauce and rocket to the pasta and mix everything. Crumble gratinated ricotta over it.
Sprinkle with parmesan.