Remove the preferred white/dark meat from the rotisserie chicken. (You do not need to pick the bones clean.) Add the carcass to the Instant Pot.
Chop the carrots and celery into roughly three inch pieces. Roughly chop the onion into large sections. Add these around the chicken bones.
Cover with water (or combination of broth and water) close to the 1/2 fill line located inside the pot. Try to keep all of the ingredients below the water surface. Do not exceed the max fill line.
Add salt and pepper.
Secure the lid on the pressure cooker. Set to manual for thirty minutes. Carefully perform a quick release when the timer goes off.
Use tongs to carefully remove the large pieces of bones and vegetables. Use a fine sieve to strain out any remaining impurities.
Makes approx 32oz of stock. Please note that there is no way for me to calculate the nutritional value of the "chicken carcass" or bones used. The numbers below include a whole rotisserie chicken. Please use these nutritional facts as a guide only.