I adore chili rellenos but when I don't want to go to all the fuss of making them I make a Roast Beef and Green Chili Panini instead.
To start you need a really good firm sourdough bread.
Panera Bread makes a lovely sourdough that won't get soggy or fall apart while cooking. Plus leftovers makes great toast for breakfast!
Next put on a nice horseradish spread, then add two pieces of provolone(one on each slice of the sandwich). The cheese on each side will act as the glue to hold all the chilies and roast beef inside.
Top one piece of the cheese with two whole green chilies that have been butterflied open.