Two days in advance, season the pork shoulder, fresh ham hock or pig’s knuckles, and the pork skin moderately with salt and pepper. Place in an earthenware or glass dish, cover, and refrigerate overnight. Soak the beans overnight in enough water to cover by at least 2 inches.
The following day, simmer the pork skin in water to cover until it is supple, 10 to 20 mi