Instructions

Heat a large sauté pan over medium heat. Add the olive oil and onion, and cook until the onion is translucent, 8-10 minutes.
Add the chile flakes and garlic, and cook for another 2 minutes, until fragrant.

Bring a large pot of salted water to a boil. Cook the pasta according to package instructions. Save ½ cup (120 ml) of pasta water, then drain.
Add the drained pasta to the sauce. Stir well, adding a little pasta water if needed to loosen the sauce. Season with salt to taste.