Slice the steak as thin as possible.
Preheat oven 350 degrees.
Butter or Mayo the Hoagie Rolls.
Bake about 15 minutes until golden brown.
Add a piece of cheese to one side of the Hoagie and return to the oven.
Remove from the oven when melted.
Heat Olive Oil and one tablespoon of butter in a pan and add thinly sliced onions.
Season with salt and pepper.
Sauté 10 minutes stirring several times until onions are soft and caramelized and then add the garlic.
Saute the onions and garlic for 5 minutes.
Add three tablespoons Worcestershire, dried thyme and mushrooms.
Stir in 3/4 cup heavy cream and 3/4 beef broth.
In a separate pan, heat Olive Oil (you could use butter) over medium high heat and add beef in a single layer.
Season well steak seasoning.
You may have to cook the beef in two batches.
Cook the beef for about 3 minutes on each side.
ASSEMBLE the steak sandwiches.
Add some mayo or horseradish to each side of the rolls.
Add some beef, onions and mushroom gravy and enjoy!
The onion and mushroom sauce is delicious, but if you add too much to your sandwich, you will have to use a fork to eat it with.