Makes about 1 quart of sauce

1 tablespoon olive oil
1 large onion, diced
3-4 garlic cloves minced
1 teaspoon celery seed
24-ounce jar of strained (or crushed) tomatoes (or a 28-ounce can)
7-ounce jar of tomato paste (or a 6-ounce can)
2 tablespoons Sriracha (if you don’t like spicy, you can skip this, add less or use just a pinch of two of red pepper flakes instead)
1/4 cup cider vinegar
1/4 cup whole grain mustard
1/4 cup maple syrup
1/4 cup blackstrap molasses
2 teaspoons liquid smoke