To be honest, this is one of the recipes I miss most while in college. It's the perfect weeknight dinner: quick, easy, and satisfying. There's carbs, meat, and gooey cheese all in one bite, plus any vegetables you want (if you want any). It's easily adaptable to your general preferences, and it's even easier to customize individually. I know some people who like peppers, sauteed onions, mushrooms, or various combinations of the three. I also know people who like provolone cheese, white American cheese, or even no cheese. My personal favorite is white American with a pile of caramelized onions.
You can't have a Philly cheesesteak without the steak. Unless you want to go with a chicken Philly cheesesteak (just repeat this process with boneless, skinless chicken breast). Anyway, I've found that both flank steak and flatiron steak work equally well; a good guideline is about 1/3 lb per sandwich. To make an authentic sandwich with tender (not chewy) meat, you have to slice the steak as thin as possible. Freezing the meat (and then letting it sit on the counter for a few minutes to soften slightly) helps tremendously with this because you can almost shave off slices, as opposed to wrangling a soft, squishy steak. A mandoline would probably work even better for thin, uniform slices, but you should definitely freeze it if you go that route. Once your meat is sliced, let it defrost fully; this should only take a few minutes since the pieces are so thin.
While your meat is freezing, you can start prepping your other toppings. Sauteed peppers, onions, and/or mushrooms are usually the most common ones (just stick your sliced veggies in a hot skillet with some oil and cook until tender), but you can get creative with bacon (always delicious), various aiolis (glorified flavored mayonnaise), fried onions, pickles, or anything else you can think of.
I love caramelized onions, and they really aren't that difficult to make. They add a sweetness that balances the salty and savory notes in the rest of the sandwich. All you have to do is slice some sweet onions into thin half-moons, throw them in a skillet with some butter, salt, and a spoonful of brown sugar, and cook them on the lowest heat for a while until they are golden brown, sweet, and tender, usually about an hour or so. I find that adding a pinch or two of baking soda instantly deepens the color. The onions brown because of a process called Maillard reactions (which are also responsible for steak sears, bread crusts, and anything else browned and delicious). When the food is basic (has a high pH), the Maillard reactions are more efficient; adding even just a pinch of baking soda (a base) drastically increases the rate of caramelization. However, it doesn't make the onions much more tender, so I tend to do this after they have reached the desired texture.
The cheese part of the sandwiches is pretty easy since I usually just get slices from the deli counter of my supermarket. As I said, I prefer white American, but my sister loves provolone; really anything that melts well is fair game. It's easy to get just a few slices of each kind at a deli counter, so make a variety and see what you like best (or even make a topping bar with all sorts of options). If you're feeling particularly adventurous, you can go with the traditional choice of Cheese Whiz. That's right. That canned orange cheese-that's-not-really-cheese is the topping of choice for purists. That's not really my thing, so I'll just leave it up to you.
To actually cook and assemble the sandwiches, heat up a skillet or griddle and add a little bit of oil. Throw on the steak slices (you'll probably have to cook them in batches) and cook until just cooked through, stirring occasionally. Once they are done, pile them on your hoagie rolls and top with your cheese and toppings. If you are making these for a crowd, wrap them in foil and throw them in a 200-250F oven to keep warm while the rest of them cook. I really wish I could make some right now because I'm practically drooling just writing about them, but they are easy enough that I might just be able to make some in the ramshackle dorm kitchen downstairs.
6 Hoagie Rolls
12 Slices Cheese
2 lbs Flatiron or Flank Steak
Onions, Peppers, Mushrooms, etc.
1 T Season Salt
2 tsp Garlic Powder
2 tsp Onion Powder
1 tsp Sugar
1/2 tsp Pepper
Freeze the steak until firm, about 2 hours. Using a sharp knife or mandoline, slice as thin as possible. Set aside.
If sauteeing onions/peppers/mushrooms, heat some oil in a skillet, add the sliced vegetables, season with salt and pepper, and cook until tender. If making caramelized onions, cut some sweet onions pole to pole, remove the papery skins, and cut into thin half-moons. Heat some butter in a skillet, add the onions, and cook over low heat until golden brown and tender, seasoning with salt and a spoonful of brown sugar. Add a pinch or two of baking soda to brown even more.
Heat some oil in a skillet or on a griddle. Add the slices of beef (cooking in batches if necessary) and cook until just cooked through, seasoning with the season salt, garlic powder, onion powder, sugar, and pepper.
Transfer the meat to the hoagie rolls and top with cheese and desired toppings.
Makes 6