Cook the macaroni noodles in a large pot of salted water according to package directions, after drain them
Heat the milk in the microwave or on the stove top until very hot but not boiling
In a sauce pot melt the butter over medium heat. Whisk in the flour and continue to cook, whisking until the mixture turns a light brown color about 2-3 minutes
Lower heat and slowly pour in the milk, whisking constantly for 3-5 minutes or until thickened
Stir in the salt, garlic powder, and the pepper
Return heat to medium heat and whisk in the cheese until fully melted
Stir the sauce into the pasta until your desired level of creaminess is reached