... that's all you need: good olive oil, garlic (or onion), pureed tomatoes, salt, pepper, chili (if you like) and time.
I got the recipe from Claudio's blog "Anonyme Köche". He is cooking and showing some pretty amazing things on his blog. But because I am not a very good cook, I love his simple recipes.
This is another favourite: "Orecchiette e Broccoli".