I make a long ingredient list for pasta sauce (I'm referring to tomato, or marinara-type, not white sauces) and I make a short ingredient list pasta sauce.
Let's go with the short-list:
2 tablespoons olive oil
1/2 cup onion, chopped (optional)
2 cloves garlic, chopped
1 can (28-ounce) whole tomatoes, any herbs packed with them removed and discarded
2 tablespoons parsley, chopped
1 bunch fresh basil, torn up or if not available, 1 tablespoon dried oregano
1/2 teaspoon each salt and pepper, or to taste
1/2 cup water, as needed
1. Place all ingredients except basil in blender or food processor. If using dried oregano, add it at this time too. Process until sauce is uniform but still chunky.
2. Heat olive oil in large saucepan until it's shimmering, but not smoking. Carefully and slowly add tomato mixture—it will spatter. ( A trick is to pour it in over the back of a spoon or spatula.) Stir and bring to a simmer. Turn heat to low and let simmer for 30 minutes, partially covered. Add water, a little at a time, to thin sauce as necessary. Adjust seasonings.
3. Remove from heat; stir in basil. Serve over warm pasta; as a sauce for baked chicken, or even as a pizza sauce.