1

Place the beans in a large ovenproof pot or Dutch oven. Add enough water to cover by 3 inches and let stand for at least 10 hours.

2

Drain the beans and return them to the pot. Add just enough water to cover the beans. Bring to a boil, then reduce heat and simmer gently until the beans are softened, about 1 hour. (Add water periodically as necessary to keep the beans barely covered.)

3

Meanwhile, in a medium bowl, whisk together the molasses, vinegar, mustard, brown sugar, pepper, and 2 tablespoons of water. Drain the beans.

4

Place the onion in the empty pot. Top with the beans, then the salt pork or bacon, then the molasses mixture.

5

Heat oven to 300'F. Cover the pot tightly and bake until the beans are tender, the bacon is falling apart, and the liquid is thick and bubbling, about 6 hours.

6

Check the beans during the last hour of cooking; if they appear to be drying out, add more water (or even a second batch of the molasses mixture). Spoon the beans into individual bowls and serve with the buttered bread.