Method:
First, start to cook spaghetti in boiling water.
In a pan, meanwhile, saute garlic and chopped chilly. After a few seconds, remove the garlic from the pan, add the tomatoes and salt. Drain the pasta and pour into the pan with the sauce, and finally into the pot by adding the chopped parsley. Season with pepper olive oil.
We can't give you indications about the quantity of chilli to use because this is subjective. Obviously more chilli and pasta place will be angry!