01 - Heat 1 tablespoon olive oil in a large Dutch oven over medium-high heat. Add chicken pieces, season lightly with salt and pepper, and cook until browned on all sides, about 4 minutes. Remove chicken and set aside.
02 - Add sausage to the pot; cook, stirring, until browned, about 2–3 minutes. Remove and set aside with the chicken.
03 - Add remaining 1 tablespoon olive oil to the pot. Sauté onion, bell pepper, and celery for 5 minutes until softened. Add garlic and cook another minute.
04 - Stir in tomato paste, then add diced tomatoes with their juices. Cook for 2 minutes, scraping any browned bits from the bottom.
05 - Add rice, smoked paprika, Cajun seasoning, thyme, oregano, cayenne (if using), and bay leaf. Stir to coat the rice and spices evenly.
06 - Return chicken and sausage to the pot. Pour in chicken broth. Bring to a boil, then reduce heat to low. Cover and simmer for 20 minutes, stirring occasionally.
07 - Uncover, gently stir, and nestle shrimp into the rice mixture. Cover and cook for an additional 8–10 minutes, until rice is tender and shrimp are pink and cooked through.
08 - Remove from heat. Discard bay leaf. Let stand, covered, for 5 minutes.
09 - Fluff rice with a fork. Garnish with green onions and parsley before serving.