Preheat oven to 300 degrees. In a large Dutch oven place the beans, chicken stock, water and epazote. Bring to a boil on the stove top. Skim off foam and cover. Bake for 90 minutes.
In a large skillet, brown the sausage then remove from pan leaving fat in the pan. Add the onion, carrots, celery and garlic to the fat. Cook over medium heat until the vegetables are tender.
After the 90 minutes of baking, remove the beans from the oven and add vegetables and sausage. Also add the chile power, cumin and salt. Stir well.