In a large bowl, take ground chicken, add all the ingredients given under meatballs, and mix. Form golf-size balls with your hands and set them aside.
Turn the Instant pot on and select the Sauté button.
Melt butter and add heavy cream, water, garlic powder, salt, nutmeg powder, and ground black pepper. Next, add the prepared meatballs and stir to coat.
Select the PRESSURE COOK button on HIGH PRESSURE for 7 minutes. (Make sure the valve is in SEALING position).
Once the pressure-cooking cycle is over, quick release pressure by manually moving the valve from SEALING to VENTING position.
Select the CANCEL button and take the lid off carefully.
Turn the Instant pot on and select the Sauté button.
Add parmesan cheese and let the sauce bubble for 5 minutes.
Select the CANCEL button.
Serve hot over pasta or with bread and enjoy.