Bring a large pot of salted water to a boil and cook the pasta according to the package directions until al dente. Reserve ½ cup of pasta water, then drain.
Season the chicken with salt and black pepper.
Melt the butter in a large skillet over medium-high heat.
Add the chicken and cook for 6–8 minutes until golden brown and fully cooked.
Stir in the minced garlic and cook for about 30 seconds until fragrant.
Pour in the heavy cream and bring it to a gentle simmer.
Stir in the Parmesan cheese, if using, until melted and smooth.
Add the cooked pasta and toss until evenly coated in the sauce.
If the sauce becomes too thick, stir in a little reserved pasta water until you reach your desired consistency.
Taste and adjust the seasoning with additional salt and pepper if needed.
Garnish with chopped parsley and extra Parmesan before serving.