Turn the instant pot to the saute high setting and add olive oil to pot
Season chicken with the salt and pepper to taste
Sear both sides until they are golden brown
Place the chicken onto a plate and set it aside
Add chicken stock to the pot and use a wooden spoon scrape the bottom of the pot to remove any brown bits stuck to the bottom
Stir in the heavy cream, garlic powder, salt, pepper
Break the fettuccine in half and layer it crosswise in about 4 layers.
Add the chicken over the pasta and place the lid on and set the valve to seal.
Turn the instant pot to pressure cook at high pressure for 7 minutes
When cooking is complete, quick release the pressure (note, if you let it natural release too long the sauce will start to burn on the bottom)
Remove the chicken breast, slice it up and toss back into the pasta
Slowly stir parmesan cheese into the pasta
If desired, cut up 4 oz of cream cheese and stir into pasta. Give it a few minutes to melt into the mixture.
Sauce will thicken as it stands.
Serve with extra Parmesan and chopped parsley if desired
Notes
If sauce start spraying out of the pressure cooker during quick release, loosely cover the valve with a towel to prevent it from spraying everywhere.
Sauce will look more soupy initially, but the pasta will absorb the liquid and adding the cheese will also thicken it up.