In a small bowl, whisk together paprika, garlic powder, onion powder, cumin, oregano, thyme, black pepper and cayenne pepper for the Cajun seasoning. Set aside
In a large heavy pot, heat olive oil over medium heat, add sausage, and sauté for 2-3 minutes on each side. Transfer to a plate.
Add onion and sauté for 2 minutes, then stir in celery and peppers, continue to sauté for about one minute, then add garlic and sauté for one more minute. Then add the Cajun seasoning and stir to coat the vegetables.
Stir in the chicken broth, tomatoes, rice, and return the sausage back into the pot. Bring to a boil, then reduce the heat to simmer and cover. Cook for 15-20 minutes, stirring 2-3 times. Add shrimp and simmer with lid on for another 3 minutes until shrimp is pink and cooked.
Garnish with green onions and parsley if desired.
