Pour 1 cup of chicken broth or water into the inner pot. The pot needs at least 1 cup of liquid to build pressure.
Place the metal trivet in the bottom of the pot. It keeps the chicken out of the liquid so it steams evenly.
In a small bowl, mix the garlic powder, onion powder, paprika, salt, pepper and Italian herbs. Drizzle the frozen chicken breasts with olive oil, then press the seasoning firmly onto both sides.
Arrange the chicken on the trivet in a single layer. If you must stack the breasts, criss-cross them and add 2 to 3 minutes to the cooking time.
Lock the lid and turn the valve to Sealing. Select Pressure Cook (Manual) on High Pressure and set the time for 12 minutes (for 6 to 8 oz breasts). See the time chart in the post for other sizes.
When the timer beeps, let the pressure release naturally for 5 to 10 minutes. This keeps the chicken tender.
Turn the valve to Venting to release the remaining steam. Keep your hands and face away from the steam.
Open the lid and check the thickest part of the chicken with a meat thermometer. It must read 165°F (74°C). If it’s lower, reseal and cook on High pressure for 2 to 3 more minutes.
Move the chicken to a cutting board and rest it for 5 minutes. Slice against the grain or shred with two forks. Spoon a little cooking liquid over the chicken for extra moisture.