1 Heat A Frying Pan, Preferably A Cast Iron One, Over Medium-High Heat For 1-2 Minutes. While The Pan Is Heating, Assemble The Sandwich, Starting With A Layer Of Bread, Then Cheese, Then Turkey, Arugula, Pickles, And Another Slice Of Bread. Butter The Side Closest To The Cheese And Place The Sandwich Butter-Side Down On To The Hot Pan To Cook. 2 Once The Bottom Of The Sandwich Is Browned, About 2-3 Minutes, Butter The Top Of The Sandwich And Carefully Flip The Sandwich Over In The Pan. Toast For Another Minute, Then Turn The Heat To Its Lowest Setting And Cover The Pan. Watch The Cheese, And When It Melts You'Re Done. Eat Immediately.