Cut raw bacon into small pieces. In a medium sized pot over medium high heat cook the bacon for about 2 minutes-it will still be raw.
Add onions and cook until bacon is cooked through-not crispy- and the onions are translucent.
Drain 1 can of the beans and add to the pot. Add the two other cans, with their liquid to the pot.
Add chili powder, salt, pepper and cayenne.
Stir until the beans are hot.
Using a potato masher mash the beans to the consistency you like.
Add cheddar cheese to beans and stir until melted.
Keep warm over low heat. If they get too dry while you are preparing other dishes just add a bit of water and stir.