From the Gulf [of Campeche] area. Bring water to a boil in a large saucepan or clay pot. Add beans, onion, and garlic. Cook at a slow boil for 1 1/2 hours or until beans are done. Add salt after 1 hour of cooking. Blend 1 cup beans in a blender or food processor with a little cooking water. Add bean mixture to remaining beans. Stir in epazote. Serve beans with chopped green onion, chile serrano, chopped cilantro, and tomato or with fresh cream and grated cheese. Makes 8 servings.