OK, now that I have them going I've refreshed my memory and can say, for every pound of beans (lima, split peas, anything you'd put with ham) 1 large diced onion, 1 tsp cumin, 1 tsp black pepper, and whatever else seems good -- maybe a bay leaf. I also have several cups of diced ham that I cut off that bone (maybe 1 cup per pound, doesn't really matter), and I'll put that in at the end so the flavor doesn't cook out of it.
I also do "refried" beans by cooking pinto beans similarly... add some beef boullion, canned tomato (diced, sauce, salsa, whatever you have), and I like 1-2 tsp cinnamon and 1/2-1 tsp cumin for every pound of beans. After pre-cooking and draining, I cook them on high for 10 minutes, then either mash them with a potato masher or wait until they cool and squish with my fingers until I like the texture. Much healthier than "real" refried beans, and much tastier than the canned version!
