Lightly toast the roll.
In a large skillet over medium heat, add the mortadella slices in two messy piles.
Fry the mortadella until it browns on the bottom, about two minutes.
Flip the mortadella piles with a spatula.
Add cheese to the top of both piles and cook for another few minutes until crisp on the bottom and the cheese has melted.
Smear your roll with the mayonnaise and mustard.
Stack up the cheesy mortadella piles and add them to the roll.
Eat this sandwich right away while it’s still crisp and melty.
