Three Cheese Tortellini And Mushroom Soup

Ingredients

• 2 tsp butter
• 2 stalks of celery, chopped
• 1 small onion, chopped
• 1 carrot, peeled &; chopped
• 2 cloves of garlic, minced
• 8 cups fat free chicken broth (vegetable broth for vegetarians)
• 2 cups water
• 5 oz shitaki mushrooms, sliced
• 8 oz baby bella mushrooms, sliced
• 1 small parmigiano reggiano rind (optional)
• 9 oz three cheese tortellini (buitoni)
• salt to taste
• 1/2 tsp fresh ground pepper
• parmigiano reggiano, grated (optional for topping)