Start by cutting the chicken into small pieces and season it with salt, pepper, and Italian seasoning. Prepare the broccoli, cauliflower, and sun-dried tomatoes by cutting them into small pieces.

In a large sauté pan, heat 2 tablespoons of olive oil over medium-high heat. Cook the chicken until it's thoroughly cooked, about 7-9 minutes, depending on thickness. Once cooked, transfer the chicken to a plate and cover it with foil to keep warm.

In the same pan, add the remaining 1 tablespoon of olive oil along with the chopped vegetables. Stir them well, then cover the pan with a lid. Lower the heat to medium and cook the vegetables for 12-15 minutes, or until they are tender.

Once the vegetables are done, remove the lid and add the cooked chicken back to the pan. Stir in the pesto and sun-dried tomatoes, mixing everything together for about 2 minutes until heated through. Serve warm, garnished with freshly grated parmesan cheese if desired.