Place frozen chicken breasts in the Instant Pot and cover with sauce. Empty can of pineapple chunks and juice on top. Close the lid and turn the knob to SEALING.
Set the timer to 25 minutes if your chicken is frozen or 18 if you chicken is thawed.
When it is done, turn the knob to VENTING. When the pressure is released, take the lid off.
Shred chicken and return to the Instant Pot so the chicken will be well coated with sauce. Serve over rice or cauliflower rice.
Sometimes I also throw in a chopped up green pepper and chopped onion . . . it tastes good with or without it.