Season your chicken with a combination of Italian Seasoning, Garlic, Salt and pepper and slice into strips.
Turn on your Instant Pot, and press the saute button. Adjust the settings to high and saute the chicken on all sides for about 3-5 minutes. Add onion about halfway through.
Turn the unit off. Using a spatula and half of the chicken stock, deglaze the bottom of the Instant Pot.
Add the penne noodles and the rest of the chicken stock.
Replace the lid and lock it in place. Make sure you vent is sealed.
Press your manual button and change the settings to 4 minutes. Release the pressure.
Open the lid, and gently stir in the cream cheese, butter, heavy cream, Parmesan and Italian Seasoning.
After everything has melted, taste test to see if you need to add anything like more garlic, Parmesan, or Italian Seasoning. Serve and Enjoy your Instant Pot Creamy Garlic Parmesan Chicken Pasta.