Adjust toaster oven cooking rack to the lowest position. Place your baking sheet inside the toaster oven and preheat it to 450°F on the “Bake” setting.

Spread the outside of each slice of bread with butter. Place one piece of bread buttered-side-down on a cutting board and top with cheese slices. Top with remaining bread slice, buttered-side-up.

Using oven mitts, carefully remove the preheated pan. Place the sandwich on the pan and return to the toaster oven.

Cook sandwich until the bottom is toasted and browned, about 4 minutes. Carefully remove the pan again, flip the sandwich with a spatula and return to the toaster oven for another 3 to 4 minutes or until the second side is browned and the cheese is melted.

Cool slightly, then slice in half and devour.