Make this recipe in a 6-1/2 quart slow cooker. If you are using a smaller cooker, cut the recipe in half.
The night before you wish to serve this soup, turn on the slow cooker to "high" and boil 12 cups of water in your microwave oven or on the stovetop, and pour into the pot of the slow cooker and cover. Check beans and discard any extraneous matter (small stones, etc.) found. Rinse beans under running water. (Use a sieve to rinse one cup of beans at a time.) Add rinsed beans to the covered slow cooker. Check water level and stir beans before retiring for the night. Turn slow cooker setting to "low."
In the morning, turn setting on the slow cooker up to "high," and add seasonings to the cooked beans.
In a microwaveable dish with cover, add onion, garlic, and bell pepper, and heat them until tender. Add to the slow cooker. Peel, wash and cut the sweet potatoes into 1/4 to 3/8 inch cubes, heat until tender, and add to slow cooker.
Stir well and cook for a half hour or longer until the contents of the slow cooker begins to boil around the edges, and then reduce the heat to "low".
Add raisins and walnuts about 1/2 hour before serving, stir, and cook for a few more minutes.
This dish may be eaten as a stew, or as a soup, if more boiling water is added to desired consistency.
Parsley, as garnish, may be used on top of soup when served.
Please Note: Nutritional values listed may vary from final results depending on actual measurements and brands used to prepare the recipe.