shop bought ones are vile as they salt is added before they have finished cooking in my opinion. in the caribbean beans are cooked till they skins begin to split and only then is the salt added . add the salt too soon the skin stays tough. not a problem if you are making refried beans I suppose but not nice for chili or rice and beans.
my ingredients in the pot are onions, garlic, thyme or oregano, black pepper about an hour before they'll be finished. once they are finished, I add salt.
for refried beans, more onions and sometimes coriander leaf too if I am making breakfast burritos. What goes into my burritos depends on what is in the house. It invariably has a tomato salsa base.
I also agree that shop bought tortillas are just wrong.
Scootergrrl, soak the beans for overnight or 6 hrs, bring to a boil, turn down the heat and leave the lid on just a bit so it simmers away. top up with water till they are 'done'. An say half way to done or nearly done, add spices add salt when they are done.
You can make a good bean soup/starter by blending some beans and its 'caldo' in a kitchen blender add some of the spices which me and or MFM have said and serve with a dash of sour cream as a garnish. Serve with either Nachos, flour or maize tortillas.