Cook the fettuccine according to package instructions until al dente.
Heat olive oil in a large skillet over medium heat.
Add the chicken breasts and cook until golden brown on both sides and fully cooked through.
Remove the chicken from the skillet and allow it to rest, then slice.
In the same skillet, sauté the minced garlic until fragrant.
Pour in the heavy cream, stirring to combine, and bring it to a gentle simmer.
Gradually whisk in the grated Parmesan cheese until melted and smooth.
Season the sauce with salt and pepper to taste.
Combine the cooked fettuccine with the sauce, adding reserved pasta water as needed.
Add the sliced chicken on top and garnish with parsley if desired.
