Prepare all ingredients: slice chicken, mince garlic, break fettuccine, and grate Parmesan.
Set Instant Pot to 'Sauté' mode and melt butter.
Sauté chicken for 3–4 minutes on each side until lightly browned.
Add minced garlic and sauté for 30 seconds.
Layer broken fettuccine over chicken in a crisscross pattern.
Pour in chicken broth and heavy cream, ensuring not to stir.
Close and seal the Instant Pot, set to 'Pressure Cook' for 8 minutes.
Perform a quick release after cooking.
Stir in grated Parmesan cheese gradually to create a creamy sauce.
Adjust sauce consistency if needed and season to taste.
Garnish with parsley or red pepper flakes and serve hot.
