Sort through the beans and discard any rocks or shriveled beans
Rinse the beans and drain well
Add beans to a wide saucepan or pot and cover with at least 12 cups of water, or so the water level is 2" above the beans
Add the roughly chopped onion and 2-3 tablespoons of lard (or oil)
Bring to a boil. Reduce heat to a simmer and let simmer for 2-3 hours partially covered. Ensure that the water level is well above the beans by adding more water if you need to (I added an additional 4-6 cups of water to this batch).
Start biting into them after 1 1/2 hours. If they are hard or grainy they need a little more time.
Once done add 1 teaspoon of salt and simmer for another 10-15 minutes. Take a final taste for salt. (I added another generous pinch to this batch).
If you want, portion into 1 cup sized bags (or jars). Include plenty of the broth in the portion bags.