Preheat the oven to 350°F and lightly grease an 11x7 (or 2 quart) casserole dish with cooking spray.
Cook elbow macaroni as directed on the package. Once done, drain and set aside.
In a saucepan over medium heat, melt butter. Whisk in flour, to create a roux, cooking and stirring for about 2 minutes.
Slowly stir in milk and bring to a boil. Continue to cook, stirring frequently, for about 3-5 minutes, or until the sauce has thickened.
Stir in Velveeta, garlic powder, onion powder, and garlic salt with parsley flakes. Cook until melted. Stir in cooked macaroni and mix to combine.
Pour the cheesy pasta into the prepared baking dish and sprinkle with shredded cheddar cheese.
Mix Panko crumbs and melted butter together and sprinkle over the casserole.
Bake for 18-20 minutes or until heated through.