Prep everything first: Dice the bell peppers, thinly slice the red onion, mince the garlic, and chop parsley. Slice the smoked chicken sausage and cut chicken into bite-sized pieces. Pat the shrimp dry with paper towels.

Bring a large pot of salted water to a rolling boil. Add penne and cook according to package directions until just al dente, usually 9–11 minutes. Reserve 1 cup of the pasta cooking water before draining.

In a bowl, toss the chicken pieces and shrimp with 1 tablespoon of Cajun seasoning, a pinch of salt, and black pepper.

Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add chicken pieces and cook 3–4 minutes per side until golden. Remove to a plate.

Add sliced sausage to the pan and sauté 2–3 minutes until caramelized; remove and set aside.

Add oil if needed, then shrimp in a single layer. Cook 1–2 minutes per side until pink and opaque. Remove and set aside.

Lower heat to medium. Add remaining oil, bell peppers, and onion. Sauté 4–5 minutes until softened. Add garlic and remaining Cajun seasoning; cook 30–45 seconds until fragrant.

Pour in heavy cream and scrape the bottom of the pan. Bring to a gentle simmer, then stir in Parmesan until melted. Adjust with reserved pasta water if too thick.

Return chicken, sausage, and shrimp to the skillet. Add drained penne and toss to coat. Cook 1–2 minutes to warm through. Adjust seasoning.

Stir in chopped parsley for freshness. Transfer to a warm serving dish and garnish with additional Parmesan and parsley.