You may have better luck asking on a diet forum, but a quick Google showed these two that look pretty good...
Sugar-Free Barbeque Sauce Recipe #1
* 1 onion finely chopped
* 1 tablespoon water
* 1 can of chopped tomatoes
* 1 tablespoon of tomato puree
* 3 tablespoons of cider vinegar
* 3 tablespoons Worcestershire sauce
* pinch of chili powder
* pinch of cinnamon
* pinch of paprika
* salt and pepper all to taste.
Put the onions in a non stick pan with just a little bit of water (maybe 1 tbsp.). Cook the onions very gently for 1-2 hours, just until the onion starts to brown. Don't let the onions burn--we are trying to caramelize the onion to bring out its natural sugars. This is the ingredient that adds the sweetness to the tomato barbeque sauce.
The second recipe uses an artificial sweetener from a diet soft drink.
Sugar-Free Barbeque Sauce Recipe #2
* 1 tablespoon dried onion flakes
* 1 teaspoon Worcestershire sauce
* 1 teaspoon lemon juice
* 1 teaspoon onion salt
* 1 teaspoon crushed garlic
* A pinch of cayenne pepper
* 4 tablespoons tomato puree
* 1 cup sugar-free cola
Simply mix these ingredients together. The sweetness comes from the diet-cola.
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