Rinse beans and sort, discarding any blemished ones.

In a large Dutch oven or stockpot, cover beans with 3 times their volume of water.

Bring to a boil; boil gently for 2 minutes.

Remove from heat; cover and let stand for 1 hour.

Drain and discard liquid.

Return soaked beans to pot along with 3 times their volume of fresh water.

Bring to a boil; reduce heat and simmer covered for 30-45 minutes or until tender.

Drain, reserving 2 cups cooking liquid.

Dice bacon.

In another bowl, using a potato masher, mash tomatoes in their juice.

In a bean pot, combine beans, reserved cooking liquid, bacon, tomatoes, onions, ketchup, molasses, sugar, mustard, salt, and pepper.

Bake, covered, in a 300 F oven for 2 1/2 hours.

Uncover, add maple syrup, and bake for 1-1 1/2 hours longer or until the sauce is thickened and coats the beans well.