Follow these simple and easy steps to create an incredible Easy Tuna Melt that will impress anyone who takes a bite:

1. Preheat the Griddle: Preheat your griddle or frying pan over medium heat.
2. Prepare Tuna Mixture: In a medium bowl, combine the drained tuna, mayonnaise, Dijon mustard, green onions, salt, and pepper. Mix well until fully combined.
3. Assemble the Sandwich: Lay out two slices of bread on a clean surface. Spread a generous amount of the tuna mixture on top of each slice.
4. Add Cheese: Place a slice of cheese over the tuna mixture on each sandwich.
5. Top with Bread: Place the remaining two slices of bread on top of the cheese to form a sandwich.
6. Butter the Bread: Spread butter or margarine evenly on the top of each sandwich.
7. Cook the Sandwiches: Place the sandwiches, buttered side down, on the preheated griddle.
8. Cook Until Golden: Cook for about 5-7 minutes or until the bottom is golden brown.
9. Flip and Finish Cooking: Carefully flip the sandwiches, and spread butter on the uncooked side. Cook the other side for another 5-7 minutes until golden and the cheese is melted.
10. Serve Immediately: Remove the sandwiches from the griddle, slice them in half, and serve hot.