You either work with several large pans or prepare the “eggs in a basket” one after the other.
Heat the butter. Use a glass to make a circular hole in the middle of the sandwich slices. Put the bread in the pan and fry a little. Place a raw egg in the middle and season with salt and pepper as desired. Let the egg freeze and turn everything once so that it is fried.
It is served pure, with ketchup, cheese (can be melted with it) or jam or tomatoes.