Beef Heart is inexpensive and lean, but it's unusual to find in the grocery. My recipe is the only version I know of that is southwest style, in fact, this is fusion cuisine, because this is not an authentic southwest recipe. Mole adds a wonderful richness to this dish. You might want to make a pan of cornbread, it's great with this. Serve with red wine, and a salad of jicama, cabbage, and celery.