Preheat oven to 350 degrees.
Pour the entire contents of one 15 oz. can of pinto beans with its juices into a covered baking dish.
Combine water with the cornstarch in a small bowl and stir until dissolved. Stir this mixture into the beans.
Add all of the remaining ingredients to this mixture and stir until well incorporated.
Cover the dish and bake for 90 minutes (yes, 90 minutes) stirring at least every 30 minutes. It will reduce and thicken substantially.
Let sit for 5-10 minutes after removing from the oven prior to serving.
This recipe can easily be doubled. Makes about four 1/2 Cup servings.