This recipe, adapted from "Jasper White's Cooking From New England" (Harper & Row; 1989), may well be the ultimate American baked bean, just sweet enough from molasses and maple sugar. Pick through beans and discard off-colored or broken ones. Rinse and drain beans. Remove rind from half of salt pork. Cut into 1 cm squares. Cut other half into 0.75to 3 cm thick strips to equal 4 or 5 strips, with rind attached. Set aside. Line bottom of earthenware crock or bean pot with 1 cm squares of salt pork and onion. Place beans on top. Bring 1 litre water to boil in saucepan. Add garlic, tomato puree, salt, pepper, mustard, maple sugar, molasses, bay leaves and vinegar. Simmer 1 minute. Mix well and pour over beans. Score strips of salt pork crosswise, about every inch, without cutting through. This prevents strips from curling while cooking. Place strips on top of beans and liquid. Cover pot and bake at 250'F. 5 hours, checking occasionally (first at 2 hours, then every hour), to be sure liquid is just barely covering beans. Add more water as needed. After 5 hours, remove cover of bean pot and cook 1 hour more. Remove strips of salt pork and stir pot before serving. Makes 6-8 servings.