Creamy Vegetable Soup

I tasted this delicious soup in a restaurant, and when I couldn't persuade the chef to share the recipe. I began to experiment on my own. Finally, I came up with this blend, which is very close to what I'd tasted. The secret ingredient, I think, is sweet potatoes!
Audrey Nemeth, Mount Vernon, Maine12-16 ServingsPrep/Total Time: 30 min.
Ingredients
- 1 large onion, chopped
- 1/4 cup butter
- 3 medium sweet potatoes, peeled and chopped
- 3 medium zucchini, chopped
- 1 bunch broccoli, chopped
- 2 cartons (32 ounces each) chicken broth
- 2 medium potatoes, peeled and shredded
- 1 teaspoon celery seed
- 1 to 2 teaspoons ground cumin
- 2 teaspoons salt
- 1 teaspoon pepper
- 2 cups half-and-half cream
Directions
- In a stockpot, saute onion in butter until transparent but not
- browned. Add the sweet potatoes, zucchini and broccoli; saute
- lightly for 5 minutes or until crisp-tender. Stir in broth; simmer
- for a few minutes. Add potatoes and seasonings; cook another 10
- minutes or until vegetables are tender. Stir in cream and heat
- through. Yield: 12-16 servings (4 quarts).