Select “sauté” on the Instant Pot and adjust to “normal.” Add 1 tablespoon of vegetable oil to the pot. When hot, add the chicken. Cook for 5-6 minutes, or until browned. Using a slotted spoon, transfer chicken to a bowl (leave oil in the pot).
Add celery, onion, bell pepper, Cajun seasoning, garlic, and salt to the pot. Cook, stirring constantly, for 3-5 minutes, or until the vegetables are softened. Press “cancel.”
Add chicken, tomatoes in their juices, 1 cup of broth, and tomato paste to the pot. Secure the lid on the pot. Close the pressure-release valve.
Select “manual” and cook at high pressure for 10 minutes. When cooking is complete, use a quick release to depressurize. Press “cancel.”
Select “sauté” and adjust to “normal.” Add the shrimp to the pot and cook for 5 minutes, or until shrimp are cooked through (they will turn pink and you’ll know they’re done). Press “cancel.”
Ladle the jambalaya over the rice and garnish with parsley or green onion.
Optional: If you’d like to add sausage to your jambalaya, you can do so by browning sliced kielbasa in the Instant Pot at the same time as you brown the chicken. Remove the chicken and sausage as instructed above, and proceed with the rest of the cooking instructions above.