Heidi'S Fried Cheese Sandwich - cooking recipe

Ingredients

2 slices bread, thick (preferably bakery, but sandwich bread will do if nothing else is available)
butter
enough swiss cheese, to make a thick filling (the real stuff, I suppose cheddar would be good too, but Heidi's grandfather always gave her gruyer)
1 egg
3 tablespoons milk or 3 tablespoons cream
salt and pepper

Preparation

Butter the bread generously and layer the cheese between the two pieces.
Beat the egg with the milk in a container large enough to contain the sandwich and season lightly (don't forget the cheese has salt too).
Allow the sandwich to absorb the egg/milk mixture- turn over 1/2 way through so the other side absorbs some too.
This should take about 10-15 minutes so as much of the custard is absorbed as possible.
Drop a tablespoonful of butter into a skillet (cast iron is best), on medium heat.
When it bubbles and smells very fragrant, add the sandwich and fry on both sides till a lovely dark-golden-brown and the cheese is all gooey and melted.
Put it on your best plate, pour yourself a big glass of milk, get out a fork and knife and enjoy.
Note: The texture of this is not like a regular grilled sandwich as the bread becomes moist and puffy because of the egg/milk soaking.