Chop the garlic and chili pepper into small pieces. (The amount of chili you add is a matter of preference. You can substitute dried red pepper flakes if necessary.) In a large skillet, fry the garlic and pepper in the olive oil until golden. Be careful not to burn the garlic. Puree the tomatoes and add them to the garlic and pepper. Cook for 30 minutes over low heat. Add salt to taste.
Add salt to a large pot of boiling water. Cook the pasta until al dente, drain it, and add it to the tomatoes. Sprinkle with parsley and serve immediately.
p.s. One would typically not sprinkle cheese on this dish, as it is thought to compete with the other flavors.