Cook the Pasta:
Bring a large pot of salted water to a boil. Add the rotini pasta and cook according to package instructions (usually about 8-10 minutes). Drain and set aside, reserving a bit of pasta water for later use.

Cook the Chicken:
While the pasta is cooking, season the chicken breasts with salt, pepper, garlic powder, and Italian seasoning.
Heat olive oil in a large skillet over medium-high heat. Add the chicken breasts and cook for 5-6 minutes per side, until golden brown and cooked through (internal temperature should reach 165°F). Remove the chicken from the skillet and set aside to rest.

Make the Garlic Butter Sauce:
In the same skillet, melt the butter over medium heat. Add the minced garlic and cook for about 1 minute, or until fragrant.
Pour in the chicken broth and bring to a simmer. Let the broth reduce for 3-4 minutes.
Stir in the heavy cream and bring to a simmer again, cooking for an additional 2-3 minutes. Add the Parmesan cheese and stir until the sauce thickens and becomes creamy. Adjust seasoning with salt and pepper as needed.

Combine the Chicken and Pasta:
Slice the cooked chicken into thin strips or bite-sized pieces. Add the cooked rotini pasta to the sauce and toss to coat evenly. If the sauce is too thick, add a little bit of the reserved pasta water to thin it out.

Serve and Garnish:
Top the pasta with the sliced chicken and give everything a final toss. Garnish with fresh parsley if desired. Serve immediately and enjoy!