2 tablespoons margarine
2  onions, chopped
1  celery stalk, with leaves, diced
2  carrots, peeled and diced
6 cups sweet potatoes, peeled and cut into 1/2-inch pieces
1/2 cup water (up to 3/4 cup if needed)
2  bay leaves
1/4 teaspoon ground {nutmeg}
1/4 teaspoon thyme
1 cup skim milk
 salt, to taste
 pepper, to taste

In a stock pot heat the margarine and sauté the onions, celery, and carrots over low heat. Add the celery leaves and sweet potatoes. Add 1/2 cup to 3/4 cup of water. Add the bay leaves and seasonings. Cover and simmer about 25 minutes until the sweet potatoes are tender.

Discard the bay leaves. Remove the solid vegetables and purée in a food processor. Add back to the stock pot. Add the milk and season to taste with salt and pepper. Simmer over low heat for 15 minutes.