First, you will need two slices of white bread. Spread butter on one side of bread and mayonnaise on the other.
Heat a pan and add one slice of bread butter side down. Then, add cheese, leftover turkey, cranberry sauce, mashed potatoes, gravy and spinach. Add the second slice of bread butter side up and cook for 2-3 minutes.
Flip the sandwich and cook for another 2-3 minutes on the other side. Slice in half and enjoy! :)
Notes
Cheese: Feel free to use brie, cheddar or Swiss cheese.