Bean based stew. Alternative to tomatoe sauce The basic bean meat chilli is as follows

Brown Garlic + Onion + ground meat (any) + boiled beans + tomato sauce + spices (e.g. chilli powder etc). 

Now I want to know if there another sauce that can swap out for tomato sauce if I get tired of it. I need something suitable for students or working professionals who don't have the time to "make their own special sauce". But tomato sauce just seems to be a good combination of liquid + thickening agent that I don't know what can be its equal.

Sorry if the tags aren't accurate, I wasn't sure what would be appropriate.
I found I'd run out of chopped tomatoes when half way through making 3 bean &amp; sweet potato chilli. I did add a little tomato puree, but only had a little of that, so had to find a substitute sauce. 

The bulk of the liquid I used was beer, quite a bitter, tasty beer. I used more cocoa powder than normal (I always use some), and a bit of extra garlic. I thickened it a little towards the end, with just a bit of cornflour, and took some of the sweet potato out, mashed it and returned it for further thickening. I often use a little beer in chilli sauce, but not normally as the bulk, so long as I did some thickening.

A blended, slow-cooked, onion-based sauce, as is used as the base of some curries, should work nicely. This is something I make, and haven't seen it sold, but it freezes well.