That left one final method, which is the one you’ll most commonly see, including in many old recipes: par-cooking the beans in water, then mixing them with the molasses and other ingredients, transferring them to the oven, and cooking for several hours more until done. It’s a method that works, but there are a few key steps needed along the way for the beans to come out just right.
While the beans are cooking, I prep the other ingredients, cutting the salt pork into large chunks, dicing the onion, and combining the molasses with the mustard, salt, and plenty of freshly ground black pepper.
Molasses is very thick, which makes it difficult to combine with the beans. The solution: As soon as the beans are done, take a couple of cups of the bean-cooking liquid and mix it with the molasses to thin it out. A lot of recipes have you drain and discard the cooking water and replace it with fresh water, but that’s a terrible idea. That bean water is loaded with bean starch and flavor, two things you absolutely want to keep in the bean pot.