Spread mayonnaise on one side of each bread slice. Layer ham, provolone cheese, and roasted red bell pepper on the bread; top sandwich with the other bread slice, mayonnaise side down.
Heat grill pan over medium heat; place sandwich in the pan and top with another heavy pan. Add 2 heavy cans on top; press down on cans to compress the sandwich. Reduce heat to medium; cook for 3 to 4 minutes. Flip sandwich, replace the pan and cans; cook until cheese is melted, 3 to 4 minutes more.
