For the Pasta

• 16 oz. penne pasta

For the Chicken

• 16 oz. boneless skinless chicken breast, cut into 1/2” cubes
• 1 1/2 tsp Cajun seasoning
• 1 Tbsp unsalted butter

For the Sauce

• 4 Tbsp unsalted butter divided
• 1 Tbsp olive oil
• 1 red bell pepper sliced into 1/4” strips
• 1 green bell pepper sliced into 1/4” strips
• 1/2 large red onion sliced into 1/4” strips
• 1 1/2 tsp minced garlic
• 1 tsp Cajun seasoning
• 1/2 cup all-purpose flour
• 2 cups low-sodium chicken stock
• 3/4 cup whole or 2% milk
• 1 head roasted garlic (10–12 cloves, coarsely chopped)
• 1/2 tsp salt
• 1/2 tsp black pepper
• 1 cup grated Parmesan cheese
• 3/4 cup heavy cream
• Green onions, chopped, for garnish