Sauté the Sausage: Select the Instant Pot sauté function and add 1 tablespoon of vegetable oil. When the oil is hot but not smoking, add the sliced sausage. Cook for about 3 to 4 minutes, stirring frequently, until lightly browned on both sides. Remove the sausage to a plate and set aside. 

Sauté the Chicken: Add the remaining tablespoon of oil to the pot. Add the chicken pieces and cook for 4 to 5 minutes, stirring occasionally, until lightly browned. Transfer the sausage to the plate. Cook the Vegetables and Aromatics: Add the onion, bell pepper, and celery to the pot. Sauté for about 5 minutes, stirring frequently, until the onion is translucent. Stir in the garlic, Creole seasoning, and black pepper. Cook for 2 more minutes, stirring often. 

Deglaze, Add Remaining Ingredients, and Pressure Cook: Pour in the chicken stock and scrape up any browned bits from the bottom of the pot. Return the sausage and chicken to the pot. Add the rice, pressing it gently into the liquid without stirring. Spoon the tomatoes with their juices on top—do not stir. Lock the lid in place, choose pressure cook, and set the time for 7 minutes. When the time is up, let the pressure come down naturally for 5 minutes and then do a quick release. 

Finish the Dish: Taste and add salt, as needed, then stir in the green onions. 

Serve: Spoon the jambalaya into bowls or a serving dish and garnish with chopped parsley, fresh thyme leaves, or sliced green onion tops. Enjoy!