Preheat oven to 450 and move rack to the upper third of the oven.
Cook macaroni al dente, according to package directions. During the final 30 seconds of cooking time add the broccoli florets to the pot. Drain and place in a GoodCook Ceramic Baking Dish.
While the pasta cooks, combine milk, fontina cheese, flour, garlic, salt, dijon, and cayenne in a blender. Pulse, then blend to combine. Pour mixture into empty pasta pot and whisk over medium heat. After a few minutes, when sauce is gently simmering, smooth, and thickened, pour over macaroni and broccoli to the pot. Stir to combine. Top with panko, remaining fontina, and Parmesan cheese.
Bake for 15-20 minutes or until the topping is crusty and golden.