I slathered one slice of sourdough bread with Dijon mustard and the other slice I coated with mayonnaise. I topped the slice of bread coated with mustard with thin slices of fresh roasted turkey, topped the turkey with 2 slices if Swiss cheese and topped the Swiss cheese with thin slices of baked ham. I topped this with the other slice of bread, mayonnaise side facing ham.
Then I dipped the sandwich in a combination of beaten egg and milk (about 1 egg to 1 tablespoon milk) and let each side soak - just as you would if you were making French toast, until all the egg mixture is absorbed. I cooked it over medium high heat in a little bit of canola oil (butter gives it a richer flavor, whatever you choose is a matter of preference) and cooked it just like a grilled cheese sandwich.
Before serving, I dusted the sandwich with a wee bit of confectioners sugar. Prior to taking each bite, we doused our Monte Cristos into homemade cherry preserves I'd made when cherries were in season in early summer. A good store bought cherry preserve like Bonne Maman will also work.