This is really easy, and delicious. Mom liked it so much when we made it while she was visiting recently that she asked for the recipe but she didn’t know that it was already in this book - ha! Also for Rachel we subbed the steak with portobello (portabella? the Internet doesn’t really agree on how to spell this word) mushrooms sliced very thin.
Cook steak in skillet until no longer pink to your desired level of done-ness, about 12-20 minutes. Remove from skillet. Cook pepper & onions in butter (or in the meat grease if you’re so inclined.) Preheat oven to 350. Slice bread length wise and add steak, peppers, onions, cheese. Broil for a couple minutes until cheese is melted. You can add banana peppers if you want. #definitelyaddthebananappers