Prep and marinate the chicken: Pat the chicken breast dry. Season both sides with salt, 1 tsp smoked paprika, 1 tsp garlic powder and 1/2 tsp ground black pepper. Add 1 tbsp oil, rub to coat, and let marinate for 30 minutes.

Cook the pasta: Bring a large pot of generously salted water to a boil. Cook the fettuccine until al dente (follow package time, typically 8–10 minutes). Reserve 1 cup (240 ml) of pasta water, then drain the pasta.

Cook the chicken: In a large skillet over medium-high heat, add 2 tbsp oil. Add the marinated chicken and cook 4–5 minutes per side (depending on thickness) until cooked through and nicely browned. Remove the chicken from the pan and set aside to rest; slice when slightly cooled.

Start the sauce: In the same skillet over medium heat, add 4 tbsp butter. Once melted, add 1 tbsp chili oil and cook 30 seconds.

Thicken the sauce: Sprinkle in 2 tsp all-purpose flour and whisk constantly for 30–40 seconds to cook out the raw flour taste (do not let it brown).

Add cream and seasonings: Gradually whisk in 1 1/2 cups heavy cream. Stir in salt to taste, 1 tsp garlic powder, 1/2 tsp ground black pepper, 1 tsp dried parsley and 1 tsp smoked paprika. Simmer gently, stirring, for 3–4 minutes until slightly thickened.

Finish the sauce: Reduce heat to low and stir in 3/4 cup freshly grated Parmesan until melted and smooth. Add 2 tsp lemon juice, taste, and adjust salt or lemon as needed.

Combine pasta and sauce: Add the drained fettuccine to the sauce. Toss gently, adding reserved pasta water a little at a time until the sauce is silky and coats the pasta (use as much as needed).

Add chicken and finish: Add the sliced chicken to the pasta and toss. Simmer on low for 1–2 minutes to let flavors meld.

Serve: Plate the pasta and garnish with extra grated Parmesan, chopped parsley and more chili oil if desired. Serve immediately.