4 ripe organic tomatoes (preferably plum tomatoes)
One 12-ounce can of San Marzano or organic whole tomatoes
2 tablespoons extra virgin olive oil
Pinch of crushed red chili pepper flakes
Kosher salt and freshly ground black pepper
2 tablespoons unsalted butter
1 ounce freshly grated Parmigiano-Reggiano (about 1/2 cup)
6 to 8 fresh basil leaves, well washed and dried, stacked and rolled into a cylinder and sliced thinly crosswise into a chiffonade
1 pound spaghetti, either high-quality dry or homemade