Cream of Asparagus Soup

One of my favorite soups. I make it as soon as fresh asparagus is available.

Ingredients

• 1/4 cup margarine
• 1 onion, chopped
• 3 stalks celery, chopped
• 3 tablespoons all-purpose flour
• 4 cups water
• 1 (10.5 ounce) can condensed chicken broth
• 4 tablespoons chicken bouillon powder
• 1 potato, peeled and diced
• 1 pound fresh asparagus, trimmed and coarsely chopped
• 3/4 cup half-and-half
• 1 tablespoon soy sauce
• 1/4 teaspoon ground black pepper
• 1/4 teaspoon ground white pepper