1. Preheat your oven to 375°F (190°C).

2. Shred or dice the cooked chicken breast; set aside.

3. Heat olive oil in a large oven-safe skillet or large pot over medium heat. Add the diced onion and cook until softened, about 3-5 minutes. Add the minced garlic and diced red bell pepper, cooking for another 2 minutes until fragrant.

4. Stir in the chopped broccoli and cauliflower florets. Sauté for 5-7 minutes until tender-crisp.

5. Reduce heat to low. Add the softened cream cheese, stirring constantly until melted and smooth. Gradually pour in the heavy cream and chicken broth, whisking until the sauce is smooth.

6. Stir in the Italian seasoning, salt, and black pepper. Taste and adjust seasoning as needed.

7. Gently fold in the cooked chicken, 1 cup of shredded cheddar cheese, and the grated Parmesan cheese until evenly coated.

8. If your skillet isn’t oven-safe, transfer the mixture to a 9×13 inch baking dish.

9. Sprinkle the remaining 1/2 cup of cheddar cheese evenly over the top.

10. Bake for 20-25 minutes, until bubbling and the cheese is melted and golden.

11. Let the casserole rest for 5-10 minutes before serving.