Start by opening the can of tuna and draining out the water.
Add to a bowl and stir in the good stuff, real mayonnaise.
Slice a tomato into thick slices.
Spread the 4 pieces of bread with the butter.
Place the bread butter side down on a griddle pan, then top with cheese and sliced tomatoes.
Add half of the tuna salad, more cheese, then butter the top piece of bread and place on top.
Repeat the process with the second sandwich.
Place the griddle pan on the stovetop and turn on the heat to medium-high.
Put a heavy pan, like cast iron, on the top of the bread so that it squishes the sandwich down. Cook for 2-1/2 minutes
Using a hot pad, remove the pan from the top of the sandwich, and set aside. Flip the sandwich, then replace the pan on top. Cook for another 2 minutes.
Take the sandwiches off of the pan. Cut diagonally.