spaghetti al pomodoro

Italian spaghetti: with„ketchup“?
As I’m abroad, I hear always something new and strange about many Italian things (life, food, country).
For example, in Germany I was really surprised to see that people eat spaghetti with ketchup! It was horrible for me!
Good, however that was long time ago: Italian couldn't eat spaghetti with ketchup!

Some people here in Germany didn’t believe me: this red thing on the top of spaghetti is just a tomato’s sauce.
Italy is a long and small (?) country, we have many regions and every region a traditional cuisine and that’s why you can find many different ways to prepare this sauce
A simple way (I mean) is to brown in a little bit olive oil a onion with garlic ( both sliced thinly) and salt (not too much, you can add it again later, if you think that it was not enough!).
When the onion is just a little bit gilded, you can add the crushed tomatoes (a can), a little bit water (just 50/50 with tomatoes) and Italian parsley.
Normally my grandma has always added water again to cook longer, but if you don’t use fresh tomatoes, I think you don’t need it!
At the end a little bit fresh basil and… Buon appetito!