In a large pot, bring salted water to a boil. Add the pasta and cook according to package instructions until al dente. Drain and set aside, reserving 1/2 cup of the pasta water.
In a large skillet over medium heat, add the olive oil. Once hot, add the diced chicken, season with salt, pepper, and Italian seasoning. Cook until browned and cooked through, about 5-7 minutes. Remove the chicken from the skillet and set aside.
In the same skillet, add the minced garlic and sauté for about 1 minute until fragrant (be careful not to burn it).
Lower the heat and pour in the heavy cream. Stir gently and allow it to simmer for about 2-3 minutes. Gradually whisk in the grated Parmesan cheese until smooth and creamy. If the sauce is too thick, add reserved pasta water a little at a time to reach desired consistency.
Return the cooked chicken to the skillet and add the cooked pasta. Toss everything together until well combined and heated through.
Plate the pasta, garnishing with chopped fresh parsley and additional Parmesan if desired.