Boil a large pot of salted water. Add the fettuccine and cook according to package instructions until al dente (9–11 minutes). Drain and reserve ½ cup of the pasta water for later.

In a bowl, toss the chicken pieces in Cajun seasoning until they are evenly coated.

Heat the olive oil in a large skillet over medium-high heat. When hot, add the chicken and cook for about 4–5 minutes, flipping halfway, until browned and cooked through. Remove the chicken and set aside.

In the same skillet, add the butter and let it melt. Once melted, add the minced garlic and sauté for about 30 seconds until fragrant—don’t let it burn! Slowly pour in the heavy cream and bring it to a gentle simmer.

Gradually whisk in the Parmesan cheese until the sauce is smooth and creamy. Season with salt and black pepper to taste. If the sauce is too thick, thin it down with the reserved pasta water.

Return the cooked chicken to the skillet. Add the fettuccine and toss everything to coat. Let it simmer together for 1–2 minutes to meld those flavors.

Optional—stir in diced tomatoes or peppers for added freshness. Garnish with parsley and serve hot!