Melt ghee in a large Dutch oven over medium heat. Add bell pepper, celery, and onion. Cook until vegetables begin to soften and onion turns soft and translucent, 3 to 4 minutes. Add chicken, sliced sausage, Cajun seasoning, and hot sauce. Cook and stir until everything is well combined, 2 to 3 minutes. Add drained tomatoes and stock and bring to a boil.
Reduce heat, cover, and simmer until chicken is cooked through, about 15 minutes. Remove lid and add riced cauliflower, breaking up any clumps while stirring. Add frozen shrimp and increase heat to medium high. Push each shrimp below the surface of the hot tomato sauce and season with black pepper. Bring to a boil and cook until shrimp curls and turn pink in color, 6 to 8 minutes.
