PLACE beans in in a large heavy pot with an accompanying lid; COVER beans with 2 inches cold water; BRING to a boil (uncovered); BOIL 2 minutes; DRAIN; RINSE well with running cold water.
RETURN beans to pot; COVER beans with cold water again; BRING to boiling again for 2 minutes uncovered; DRAIN in colander; RINSE well with running cold water; ALLOW to drain until needed.
IN the same large heavy pot over medium heat, add the bacon fat until sizzling; ADD ham shanks and cook, turning, until evenly seared, about 7 minutes; REMOVE shanks with tongs; SET aside.
ADD onions and bay leaf; COOK, stirring, for 5 minutes; ADD garlic and drained beans; COOK for just one minute, stirring.
SPRINKLE bean mixture with 4 tablespoons all-purpose flour while stirring; TOSS mixture well.
POUR in 6 cups cold water; STIR in the remaining seasonings except salt and pickled pepper brine.
BRING to a full rolling boil; REDUCE heat between low and medium-low (no higher than the numeric "2" setting on stovetop turn-dial); COVER.
SIMMER for 2 hours without lifting lid.
UNCOVER beans and stir; BEANS should be creamy and the meat should easily fall off of the bones (if desired, continue cooking and stirring uncovered, to desired consistency); CLEAN meat from bone portion of meat (discard bones); REMOVE bay leaf; SEASON beans to taste with salt and pickled pepper brine; STIR well and cook 5 additional minutes.
SERVE and enjoy!