BBQ Sauce

This is the sauce I'll be trying. I'll update on how it turns out:

1 cup finely chopped onion
1/4 cup oil
6 oz. can of tomato paste
1/2 cup water
1/4 cup brown sugar
1/4 cup lemon juice
2 tbsp.  prepared mustard
2 tsp. salt

Combine in cockpot and cook on low for 3 hours.