In a very large pot (20-qt +), soak:

8 lbs. dry black beans

for 48 hours in ample water. Remove floating beans and other imperfections, replacing water after 24 hours. Replace water once more (with enough to cover the beans in 1 inch of water). In a second pot, bring to a boil then reduce to very low heat and simmer. Stir frequently and be sure to scrape the bottom to check that beans are not sticking.

In a the very large pot saute, (in turn), over medium-low heat:

 6 tablespoons vegetable oil (such as sunflower or olive oil)
 2 sticks of butter (16 tablespoons)
 24 minced garlic cloves or 8 tablespoons minced garlic in oil
 8 lbs. finely chopped yellow onion
 12 cups finely chopped red and green bell pepper
 
After sauteing, add:

 8 tablespoons salt
 4 tablespoons ground cumin powder
 2 tablespoons ground black pepper
 4 tablespoons ground Venezuelan pimienta dulce, or Jamaican ground allspice
 8 bay leaves
 1 lb. (16 ounces) Venezuelan papelon or Colombian panela (solid dark brown sugar cane chunk or solid molasses chunk)

Stir frequently and cook until slightly reduced and golden brown. Add beans to the sauteed mixture. Stir well, return to a boil, then cover and place in a 250 degree oven for 4-6+ more hours until beans are very soft and turning into bean paste.

Serve with white or brown jasmin rice, stringed beef brisquet or pulled pork and plantains for the traditional Venezuelan pabellon. Refrigerate and/or freeze unused portion when it cools to room temperature.

Also a non-vegetarian smaller version.

 (*optional )