To make this Broccoli Cheese Soup gluten-free. Simply replace the all-purpose flour. With a gluten-free flour blend or cornstarch. If using cornstarch. Mix 1 tablespoon with a little cold water. Before adding it to the soup. To prevent clumping. Additionally, double-check that your chicken broth. And all other ingredients are certified gluten-free. To avoid any hidden sources of gluten. This small adjustment will ensure. That everyone can enjoy. This delicious, comforting soup!