Chop the garlic and onion.
Blanch the tomatoes in boiling water, peel off the skin, and dice them.
Heat olive oil in a pan and sauté the garlic and onion.
Add the tomatoes and season with salt, pepper, and chili flakes.
Simmer the sauce over medium-low heat for 10–15 minutes.
Cook the pasta and toss it with the sauce.
Finish with parsley or basil.