Bring a large pan of salted water to the boil. Add the spaghettini. As soon as the pasta is in, heat the olive oil in a large frying pan over a brisk heat, and add the garlic. Stir for about 30 seconds, then add the tomatoes. Stir and simmer, then leave to bubble, occasionally crushing down the tomatoes, for 5 minutes or so, until they form a rough sauce. Season with salt and pepper, then roughly tear the basil leaves and scatter over the sauce. Cook for 1 minute or so more. Taste and adjust seasoning.

Drain the pasta and tip into the sauce (if there's enough room in the pan - if not, tip the sauce over the pasta in the usual way). Turn carefully, to coat, then serve with freshly grated Parmesan.