Bring a large pot of generously salted water to a boil. Cook the pasta according to the package directions until al dente. Reserve 1/2 cup of the starchy pasta water, then drain the pasta and set aside.
Pat the chicken breasts dry with a paper towel. Season evenly on both sides with Italian seasoning, salt, and black pepper.
Heat the olive oil in a large skillet over medium-high heat. Add the chicken breasts and cook for 5-7 minutes per side, until golden brown and the internal temperature reaches 165°F. Remove the chicken to a cutting board, tent with foil, and let it rest for 5 minutes before slicing.
Reduce the skillet heat to medium. Add the butter and allow it to melt, scraping up any browned bits from the chicken. Add the minced garlic and sauté for 1 minute until fragrant.
Pour the heavy whipping cream into the skillet, stirring constantly. Let the cream simmer gently for 2 to 3 minutes until slightly thickened.
Remove the skillet entirely from the heat. Gradually whisk in the freshly grated Parmesan cheese until the sauce is completely smooth and luxurious.
Add the cooked pasta into the alfredo sauce, tossing well to coat. If the sauce feels too thick, splash in a little of the reserved pasta water to reach your desired consistency.
Top the creamy pasta with the sliced chicken breast. Garnish with chopped fresh parsley and additional Parmesan cheese before serving immediately.