Chop the onion and garlic and sauté in a little olive oil. Add tomato paste and pour in a dash of balsamic vinegar. Now add the tomatoes and the bay leaf and let it simmer over medium heat until the desired consistency is achieved.
In the meantime, cook the pasta in a large saucepan with boiling salted water until al dente.
Add a little sugar to the sauce if you like. Add the ricotta and basil to the sauce. Season to taste with salt and pepper and mix the drained pasta with the sauce and rocket.