I've created this sauce from a few I've tried over the years. I like my sauce zippy. You can cut down on the spices for a milder version. This sauce is truly 'ole'. Recipe makes about 5 cups of sauce. Freeze what you don't use or halve recipe for less.

3 cups purified water
16 oz tomato sauce or 16 oz diced tomatoes, pureed
1 very large onion, diced
4 garlic cloves, minced
1 1/2 T chili powder
1/2 T ground chipotle
1 tsp dried oregano or majoram
1 tsp ground cumin
1 1/2 T agave nectar sweetener
4 T cornstarch mixed with 1/2 cup cold water. (Can use arrowroot powder instead.)

Mix the cornstarch with cold water and set aside.
Dice the onion and mince the garlic. Place the onions and garlic in sauce pot. Add the other ingredients and spices through the agave nectar. (If using organic diced tomatoes, puree the tomatoes in food processor before adding to sauce pot, otherwise add the tomato sauce to the pot with onion and garlic.). Bring to a boil, then reduce heat, cover and simmer for 20 minutes. Slowly add the cornstarch mixture and mix until thick. (For a thinner sauce, puree the sauce in processor when cool.)