You’ll need a slice of your favorite bread, with just a smear of mayonnaise on it, perhaps 2 or 3 tablespoons of crushed pineapple, and about an equal amount of your favorite cheese, shredded, and a 2 or 3 ounce slice of ham cut into strips.
Heat a cast iron skillet over medium-high heat until a drop of water hops and dances on the surface. Toss in the ham and cook until heated through, maybe 2 minutes. Add the pineapple (juice too) to the ham and continue to stir for another minute or so. Top with the cheese and let it stand until the cheese starts to melt.
Lift the whole thing onto your bread (or bun) and enjoy.