Cut the chicken into 1-inch chunks and add them to the Instant Pot along with the pineapple juice, salt, pepper, and garlic powder. Stir gently to combine and ensure the chicken is mostly submerged in the liquid. This creates an aromatic base that will infuse the chicken with tropical flavor during cooking.

Close the Instant Pot lid and set the pressure valve to sealing. Cook on high pressure for 10 minutes if using fresh chicken, or 12 minutes if using frozen chicken. After the timer beeps, let the pressure release naturally for 10 minutes before manually venting any remaining steam. This natural release helps keep the chicken tender and prevents it from becoming tough.

Carefully remove the cooked chicken from the Instant Pot with a slotted spoon and set it aside on a plate. Switch the Instant Pot to sauté mode on medium-high heat. Add the BBQ sauce and soy sauce to the remaining liquid in the pot, stirring well to combine. I like to add the soy sauce because it deepens the flavor and adds a savory element that balances the sweetness of the BBQ sauce and pineapple juice. Let the sauce simmer for about 10 minutes, stirring occasionally, until it thickens slightly and the flavors meld together.

Once the sauce has thickened, shred the reserved chicken into bite-sized pieces using two forks or your hands. Stir the shredded chicken back into the sauce in the Instant Pot, making sure every piece is coated. Let it warm through for a minute or two, then taste and adjust seasoning if needed.

Transfer the shredded Hawaiian chicken and sauce to a serving bowl or platter. Serve immediately over rice, in sandwiches, or with your favorite sides. The chicken is perfectly tender and fully coated in a sweet and savory tropical sauce.