Cook the spaghetti in a large pot of salted boiling water until al dente.
Peel the garlic cloves, cut them in half, and thinly slice. Finely chop the fresh red chili peppers (removing the seeds if less spice is desired). For a more subtle garlic flavor, leave the cloves intact, proceed with step 3, and then remove the cloves before adding the pasta.
Heat the extra virgin olive oil in a large pan over medium heat. Reduce the heat to low and add the garlic and red chili peppers. Carefully sauté for a few minutes until golden and fragrant. To ensure even cooking, tilt the pan so that the olive oil, garlic, and chili peppers are all in the same portion of the pan.
When the pasta is ready, reserve some of the pasta water then drain. Add the pasta to the pan with the garlic and peppers together with 1-2 ladles of pasta water (this helps the other ingredients bind to the pasta). Mix over low heat until the flavors come together, then serve immediately. Top with fresh parsley if desired.