Tried this out, and we cracked into one of the jars the very next day. It's great, not overly sweet and perfect for whatever you want to use it for.
11 cups tomato purée
2 celery stalks, chopped
2 medium onions, chopped
1 medium red bell pepper, chopped
1½ cups chopped red chili peppers (i used jalapenos)
4 garlic cloves, minced
1 tsp black peppercorns
1 Tbs cumin seeds
1 Tbs dry mustard
1 cup molasses
1 Tbs pickling salt
1¾ cups red wine vinegar
In a large nonreactive pot, bring to a boil the tomato purée, celery, onion, bell and chili peppers and garlic. Reduce the heat, and simmer the vegetables until they are soft and the mixture is reduced by about one third.
Tie the peppercorns in a spice bag or cheesecloth and toast the cumin seeds in a dry pan until they are fragrant.
Purée the mixture through a food mill, and return it to the pot. Add the spice bag, cumin seeds and remaining ingredients. Cook the sauce until it is about as thick as ketchup, about 1-2 hours. As the mixture thickens, stir often to prevent sticking.
Remove the spice bag. Ladle the sauce in to pint or half pint jars. Seal and process in a hot water bath for 20 minutes.
I'm guessing that if you didn't want to can and process this it could easily be frozen in small amounts as well.