Select mature, dry beans. Sort out and discard discolored beans.
Soak and boil beans as follows – Sort and wash dry beans. Add 3 cups of water for each cup of dried beans or peas. Boil 2 minutes, remove from heat and soak 1 hour and drain. Heat to boiling in fresh water, and save liquid for making sauce.
Prepare molasses sauce as follows – Mix 4 cups water or cooking liquid from beans, 3 tablespoons dark molasses, 1 tablespoon vinegar, 2 teaspoons salt, and ¾ teaspoon powdered dry mustard. Heat to boiling.
Place seven ¾-inch pieces of pork, ham, or bacon in an earthenware crock, a large casserole, or a pan. Add beans and enough molasses sauce to cover beans. Cover and bake 4 to 5 hours at 350ºF. Add water as needed–about every hour.
Fill jars, leaving 1-inch headspace. Adjust lids and process in a pressure canner: 65 minutes for pints and 75 for quarts at 11lbs of pressure for a dial gauge canner and 10lbs for weighted gauge canner. Adjust for altitude using the table below in the section: "Changes in Altitudes - Dial Gauge vs. Weighted Gauge for Pressure Canners"
Makes 9 pints