To prepare this recipe gluten-free, ensure the broth is not cross-contaminated with any gluten-based ingredients (e.g., bouillon or commercial fish stock). Most of the core ingredients are naturally gluten-free. For serving, replace the traditional baguette with a certified gluten-free bread or skip it entirely and enjoy the stew as is. Be cautious with pre-packaged rouille or make your own using gluten-free breadcrumbs or none at all.