In a food processor, puree the tomatoes to a smooth creamy consistency.
Add olive oil to a large pan over medium heat. Once hot, add the onions and saute until they are soft, and before it actually starts browning a bit, add the garlic. If you'd like to make the sauce spicier, add a pinch red pepper, optional.
Add the tomatoes and season with salt and pepper.
Simmer on a medium-low flame for about a half hour. Thrive for balance in the consistency of the sauce, it has to be fluid but it should not look overly wet. A few minutes before taking the sauce off the fire, add half the basil and season with salt and pepper.
To serve: Cook a nice al dente pasta, dress with red sauce and finish with some freshly grated Parmesan, a couple of leaves of basil and sprinkle with extra-virgin olive oil.