Cook the Pasta:
Bring a large pot of salted water to a boil. Cook the pasta according to package instructions until al dente. Reserve ½ cup of the pasta water, then drain and set aside.

Prepare the Chicken:
In a bowl, toss the diced chicken with garlic powder, paprika, salt, and pepper.
In a large skillet over medium-high heat, heat olive oil and butter. Add the seasoned chicken and cook until golden brown and cooked through, about 6–8 minutes. Add minced garlic and cook for an additional minute. Squeeze lemon juice over the chicken, toss to coat, then remove from the skillet and set aside.

Make the Parmesan Sauce:
In the same skillet, melt 2 tablespoons of butter over medium heat. Add minced garlic and sauté until fragrant, about 1 minute. Pour in the heavy cream and bring to a gentle simmer. Stir in the grated Parmesan cheese and Italian seasoning, stirring until the cheese is melted and the sauce is smooth. Season with salt and black pepper to taste. If the sauce is too thick, add reserved pasta water a little at a time until desired consistency is reached.

Combine Pasta and Chicken:
Add the cooked pasta to the sauce, tossing to coat evenly. Return the cooked chicken to the skillet and gently mix to combine. Cook for an additional 2–3 minutes to heat through.

Serve:
Garnish with chopped fresh parsley and additional grated Parmesan cheese if desired. Serve immediately.