“I will stress that the order in which you assemble a sandwich can be crucial to the enjoyment. If your tomatoes slip out, it's a big mess. Cheese placed in the middle of a sandwich won't melt, and lettuce belongs around everything else,” writes cookbook author Dwayne Ridgaway in Panini and Other Great Grilled Sandwiches: Recipes for the Original “Anytime, Anywhere” Meal.
“After making hundreds [of hot sandwiches] for this book, here's my definition of the right order:”
4. Tomato or other vegetable
6. Cheese again