In a large pot with plenty of water, simmer the beans with a touch of salt until they start splitting. Skim the top regularly and add water if the level falls below the beans. Drain and reserve the liquid.
Allow the beans to cool down for 1 hour before handling. Preheat oven to 225 degrees F.
Add the beans back to the pot. Add the sliced onion, molasses, mustard, brown sugar, tomato sauce, and the remaining cooking liquid to the pot. Add more water to cover the beans if there is not enough cooking liquid. Season lightly with salt and pepper and add the bay leaves.
To make more traditional baked beans, add a chunk of salted pork flank or bacon slices.
Bake the beans, covered, for 12 hours overnight. Check in the morning to see if you need to add a touch of liquid. If not, beans are ready to eat.
Serve in bowl with toast.
This recipe was provided by professional chefs and has been scaled down from a bulk recipe provided by a restaurant. The FN chefs have not tested this recipe, in the proportions indicated, and therefore, we cannot make any representation as to the results.