In a heavy 2-quart saucepan stir together flour and oil until smooth. Cook over medium-high heat for 4 minutes, stirring constantly. Reduce heat to medium. Continue to cook, stirring constantly, for about 15 minutes more or until roux is dark reddish brown. Let roux cool.
In Crockpot
Add chicken broth to a 3 1/2 to 6-quart slow cooker and Stir in roux.
Add sausage, chicken, okra, onion, green pepper, celery, garlic, salt, pepper, and red pepper.
Cover and cook on LOW for 8 to 10 hours, or HIGH for 4 to 5 hours.
Serve with hot cooked rice.
Gluten Free
Use a gluten free flour for the roux. I used rice flour.