Combine olive oil and garlic in saucepan. Cook until garlic is soft and golden brown, about 6 minutes. Remove garlic with a slotted spoon and set aside.
STEP 2
Add onion to garlic oil and cook until translucent, about 5 minutes. Crush San Marzano tomatoes into the pot, fill can with water, and pour into sauce. Stir in crushed tomatoes, tomato sauce, tomato paste, granulated garlic, onion powder, and red pepper flakes. Season with salt and pepper.
STEP 3
Chop reserved browned garlic and add to sauce.
STEP 4
Stir in Parmesan rind and basil. Simmer sauce, stirring occasionally, until deepened in color and reduced, about 1 hour 30 minutes. Season with salt and pepper. Discard Parmesan rind and basil before serving.