1Pat the chicken breast dry and season with salt, 0.5 tsp black pepper powder, 1 tsp garlic powder, and 1 tsp smoked paprika powder. Add 1 tbsp oil and mix well. Let marinate for 30 minutes.
2Bring a large pot of salted water to a boil. Cook fettuccine until al dente. Reserve 1 cup pasta water, then drain.
3Heat 2 tbsp oil in a pan over medium-high heat. Add marinated chicken and cook for 4–5 minutes per side until cooked through. Remove chicken and set aside.
4In the same pan, add 5 tbsp butter. Once melted, add 1.5 tbsp all purpose flour. Whisk constantly for 30–40 seconds to cook out the raw taste (do not brown).
5Slowly add 1.5 cups heavy whipping cream, whisking to combine. Add salt to taste, 1 tsp garlic powder, 0.5 tsp black pepper, 1 tsp Italian seasoning, and 1 tsp dried parsley.
6Simmer gently for 3–4 minutes, stirring, until slightly thickened.
7Reduce heat to low, then stir in 0.75 cup Parmesan cheese until melted and smooth.
8Add 1 tbsp lemon zest and 2 tsp lemon juice. Taste and adjust salt or lemon if needed.
9Add cooked fettuccine to the sauce. Toss gently, adding reserved pasta water a little at a time until the sauce is silky and coats the pasta.
10Slice the cooked chicken and add to the pasta. Toss again and simmer on low for 1–2 minutes to combine.
11Garnish with extra Parmesan, parsley, or a pinch of black pepper. Optionally, drizzle a little olive oil or butter on top before serving.