Tomato and Basil Pasta Sauce

3 tablespoons extra virgin olive oil

1 large onion, chopped

2 cloves garlic, crushed

2 (14.5 ounce) cans tomatoes, chopped

¼ teaspoon red pepper flakes, or to taste

2 teaspoons balsamic vinegar

2 teaspoons white sugar

¾ cup basil leaves, torn into pieces

salt and ground black pepper to taste

Heat the olive oil in a skillet over medium heat; cook the onion and garlic in the hot oil until tender, about 5 minutes. Stir the tomatoes, red pepper flakes, vinegar, and sugar into the onion and garlic mixture; bring to a boil, reduce heat to low, and simmer until the flavors blend to your liking, 45 to 60 minutes. Stir the basil into the sauce; season with salt and pepper.