frequently, until softened but not browned, about 3
minutes. Add the garlic, oregano, and pepper flakes and
cook, stirring, until fragrant, about 1 minute.
Add the tomatoes with their juice, and the basil, if using.
Bring to a boil over high heat, reduce to a simmer, and
cook, stirring occasionally, until the sauce is thickened
and reduced to 4 cups, about 30 minutes. Season to taste
with salt. The sauce will keep in a sealed container in the
refrigerator for up to 1 week.