This was adapted from a recipe card picked up in a grocery store. Delicious - great for a cold day, with some soup! Feel free to change up the bread to what you prefer - the original called for marble rye, but I put in what we usually use. You can use other types of ham and regular cheddar, but the flavor of the smoked versions really contrast wonderfully with the sweetness of the onions and apple, so I would recommend trying them, if possible. I'm also putting a range on the meat, because we prefer smaller meat portions (the 1/4 lb), but I know a lot of people who like more meat, so you could easily use up to 1/2 lb, if desired. The original directions called for using a panini grill, but I don't have one, so I'm enclosing both methods.