Bring a large pot of salted water to a rolling boil over high heat. Add the fettuccine and cook according to package instructions until al dente, draining and reserving ½ cup of the pasta water.

While the pasta cooks, season diced boneless chicken breast with Cajun seasoning, salt, and pepper.

In a skillet, heat olive oil over medium-high heat and cook the seasoned chicken until golden brown and cooked through, about 6–8 minutes.

Reduce heat to medium, add butter, and melt completely, swirling to incorporate bits from the skillet. Add garlic and sauté until fragrant.

Stir in honey and let simmer for about 1 minute.

Pour in heavy cream while stirring to blend, cooking for 2–3 minutes until sauce thickens.

Return the cooked chicken to the skillet, mix to coat evenly in the sauce.

Add drained fettuccine to the skillet and toss gently, adding reserved pasta water as needed to reach desired consistency.

Garnish with parsley if desired and serve immediately.