Over medium heat, sauté the onion, bell peppers, and celery in butter until the onions are translucent—approximately 15 minutes.
Add the flour, stirring constantly until well blended but not browned.
Add garlic and tomato sauce, stir.
Stir in chicken broth and half-and-half.
Lower heat and simmer for approximately 10 minutes.
Add crawfish, seasonings, and green onions.
Heat through for about 15 more minutes, stirring often, allowing flavors to blend.
Notes
Serve over a bed of hot rice, with a green salad, and hot French bread or pistolettes for dipping the sauce from your bowl! Serves 6-8 depending on serving size.