Butter one side of each slice of bread and sprinkle lightly with garlic salt.
Place your American Cheese on one buttered slice of bread (so the butter is covered).
Place your Provolone Cheese on the other buttered slice of bread (so the butter is covered).
Top one of the slices of bread and cheese with the warm macaroni and cheese.
Place the other slice of bread with cheese on top of the macaroni, creating a sandwich.
Butter the top of the sandwich that is facing up. Place butter side down in your warmed skillet.
After you place the buttered side of the sandwich on the skillet, butter the other side that is now facing up.
Check the side that is toasting in the pan and flip the sandwich when it reaches the prefect toastiness (totally up to you). If any mac n cheese falls out, shove it back in the center.
After flipping, watch the side that is cooking (it will cook fast). When it reaches your desired toastiness, remove from heat, remove the sandwich from the pan (carefully) and enjoy!
Nutrition information is automatically calculated and should only be used as an approximation.