As a vegetarian, Bettigene Reiswig finds the ingredients she prefers to eat and cook with are well suited to thick, hearty, satisfying soups. She uses vegetable broth for this mixture, but suggests chicken broth for others who prefer its richer flavor.
1/2 cup thinly sliced celery
1 cup chopped onion
2 teaspoons salad oil
3 cups diced (1/2 in.) peeled yams (1 lb. total)
2 cups diced (1/2 in.) peeled, cored Granny Smith apples (8 to 9 oz. total)
3 cups fat-skimmed chicken or vegetable broth
Plain low-fat yogurt or sour cream
Salt and pepper
How to Make It
In a 3- to 4-quart pan over high heat, frequently stir celery and onion in oil until lightly browned, about 5 minutes. Add yams, apples, and broth; bring to a boil, cover, reduce heat, and simmer until yams are tender when pierced, about 15 minutes.
With a slotted spoon, transfer vegetables and apples to a blender or food processor; whirl until smooth, adding enough cooking liquid to purée easily. Pour purée back into pan and stir over medium-high heat just until steaming, 2 to 3 minutes.
Ladle soup into wide bowls. Add yogurt, salt, and pepper to taste.