Preheat oven to 375 degrees. Grease a 13X9 0r 3-quart size baking dish.
In a large pot, heat 4 quarts of water to boiling. Add the macaroni & boil for 4 minutes. Stir in the carrots, & continue to boil for 2 minutes or until tender. Drain. Return to the pasta & carrots to the large pot. Add the broccoli, alfredo sauce, and 1/2 cup parmesan cheese. Stir to combine.
Pour the pasta mixture into the prepared baking dish.
In a small bowl, add the panko breadcrumbs, remaining 1/4 cup parmesan cheese, and melted butter. Stir to combine. Sprinkle evenly over the top of the pasta mixture.
Bake uncovered for 25 to 30 minutes or until heated through and topping is golden.
Serve & enjoy!