Set aside 4 slices of the Cooper Sharp cheese. You’ll use these on the burgers, so keep them in the fridge until you’re ready for them.
Cook macaroni according to package directions.
Melt butter in a 3-quart saucepan until sizzling. Stir in flour, 1/2 teaspoon salt, and 1/8 teaspoon black pepper. Add milk and cook over medium heat, stirring constantly until mixture thickens (about 5-7 minutes).
Reduce heat to low. Stir in remaining Cooper Sharp cheese slices (not the 4 slices in your fridge), stirring constantly until cheese is melted. Add cooked macaroni and stir well.
In a medium bowl, mix ground beef, 1 teaspoon salt, and 1/2 teaspoon black pepper. Form into 4 patties.
Cook the burgers in a medium skillet for 6-8 minutes per side, or until the internal temperature reaches 165°F and burgers are browned all the way through. On two of the burgers, during the last minute or so of cooking, layer 2 slices of Cooper Sharp each. Continue heating until the cheese is as melty as you like it.
Place a piece of lettuce on the bottom section of one of the buns and add one burger patty (without cheese). Scoop a generous portion of the mac and cheese onto the burger. Layer the second burger patty (with cheese) on top of the mac and cheese. Top the burger with a condiment of your choice and place the top of the bun on the burger.