Over high heat, bring chicken broth and water, mustard, and garlic to a simmer. As this is coming to a boil, de-rib and wash the spinach, then tear the leaves into 2-inch pieces. Lightly toast 4 slices of French or Italian bread. When toasted, spread with sundried tomato, pesto or green olive paste.
When the soup is at a simmer, add the chicken and simmer, uncovered for 2 minutes just to warm through. Then add the spinach leaves, and cook for a few seconds or until the leaves just wilt. Season with salt and pepper to taste.
Set 2 slices of toasted bread in the bottom of each soup bowl. Remove the soup from the heat, season to taste with salt and pepper and ladle it over the bread.
Recipe Courtesy of �Michelle Urvater