In a hot medium sized pot, add the oil, when hot (not smoking) add onions and shallots. (Med/high heat)
Sweat until fragrant and translucent, stirring occasionally
Add the crushed tomatoes, stir and bring to a boil.
Once it comes to a boil, reduce the temperature to a simmer
Place the lid on the pot with a small vent left open
Reduce the sauce until desired consistency is reached, stirring occasionally, about 20 minutes
Add salt/pepper to taste and the basil torn into shreds.
Stir and this sauce is ready to enjoy!
Toss with your favorite pasta and serve with extra sauce, parmigiano Reggiano cheese and crushed chili peppers.