Sauté Meats: Set your Instant Pot to 'Sauté' mode on high. Add olive oil. Once hot, add chicken pieces and brown on all sides, about 3-4 minutes. Remove chicken and set aside. Add sliced sausage to the pot and cook until lightly browned, about 3-5 minutes. Remove sausage and set aside, leaving any rendered fat in the pot.
Sauté Vegetables: Add diced onion, bell pepper, and celery (the 'holy trinity') to the pot. Sauté for 5-7 minutes until softened, scraping up any browned bits from the bottom of the pot with a wooden spoon. This crucial step helps prevent a 'BURN' error later. Add minced garlic and cook for another minute until fragrant.
Deglaze and Season: Pour in about ¼ cup of the chicken broth and deglaze the pot thoroughly, ensuring no bits are stuck to the bottom. Stir in the diced tomatoes (undrained), Creole seasoning, dried thyme, and cayenne pepper (if using). Return the cooked chicken and sausage to the pot, distributing evenly.
Add Rice and Liquid: Evenly spread the rinsed long-grain white rice over the meat and vegetables. Do NOT stir the rice into the mixture. Gently pour the remaining 1 ¾ cups of chicken broth over the rice. Place the bay leaf on top. Do not stir, as stirring can release starch and lead to mushy Instant Pot Jambalaya.
Pressure Cook: Secure the lid on your Instant Pot and ensure the sealing valve is in the 'Sealing' position. Select 'Manual' or 'Pressure Cook' on High Pressure for 8 minutes. Once cooking is complete, allow a Natural Pressure Release (NPR) for 10 minutes, then carefully quick release any remaining pressure.
Add Shrimp and Finish: Carefully open the lid. Remove the bay leaf. Stir in the peeled and deveined shrimp. Close the lid (do not seal) and let the shrimp cook in the residual heat for 3-5 minutes, or until they turn pink and opaque. This method helps prevent overcooked, rubbery shrimp in your Instant Pot Jambalaya.
Serve: Fluff the Instant Pot Jambalaya with a fork, ensuring all ingredients are well combined. Taste and adjust seasoning if needed. Garnish with fresh chopped parsley before serving hot. Enjoy this flavorful and quick Creole classic that comes together so easily in your pressure cooker.