2 Tbsp olive oil
1/2 medium onion, finely chopped
1 small carrot or 1/2 large carrot, finely chopped
1 small stalk of celery, including the green tops, finely chopped
2 Tbsp chopped fresh parsley
1 clove garlic, minced
1/2 teaspoon dried basil or 2 Tbsp chopped fresh basil
1 28 oz. can whole tomatoes, including the juice, or 1 3/4 pound of fresh tomatoes, peeled, seeded, and chopped
1 teaspoon tomato paste
Salt and freshly ground black pepper to taste