The Philly Recipe

Prepare beef

If not pre-sliced, freeze beef for 20–30 minutes until slightly firm, then slice as thin as possible across the grain. Season with 1 tsp kosher salt and 1 tsp freshly ground black pepper and toss to coat evenly.

Heat a large cast-iron skillet or griddle over medium-high heat until shimmering. Add 2 tbs vegetable oil and spread to coat the pan.

Add half the beef in a single layer (do not overcrowd). Let it sear undisturbed 30–45 seconds to develop color, then use a spatula to push and chop the meat, spreading it into a thin layer to finish cooking, about 1–1.5 minutes. Remove to a bowl and repeat with remaining beef. Return all cooked beef to the pan and keep warm over low heat.

Sauté onions, mushrooms and peppers

While the beef rests, in a separate large skillet heat 1 tbs olive oil + 1 tbs unsalted butter over medium heat until butter foams. Add the thinly sliced onions and a pinch of salt. Cook, stirring occasionally, until onions soften and begin to brown, about 6–8 minutes.

Add the sliced mushrooms and continue cooking, stirring, until mushrooms release their liquid and it evaporates and both onions and mushrooms are nicely browned, about 5–7 minutes more.

Stir in the sliced hot peppers, 1 tsp minced garlic, 1/2 tsp dried oregano, 1/2 tsp salt and 1/4 tsp black pepper. Cook for another 1–2 minutes until garlic is fragrant. Taste and adjust seasoning.

If you prefer softer, more caramelized vegetables, cook an additional 3–5 minutes over medium-low heat, stirring occasionally.

Combine beef and vegetables

Add the cooked beef back into the vegetables skillet (or combine both in the cast-iron) and stir to mix. Keep the mixture over low heat so it stays hot and juicy.

Split the hoagie rolls and spread a thin layer of softened butter on the cut faces. Toast the rolls, cut-side down, in a hot skillet or on a griddle until golden-brown, about 1–2 minutes.

Pile half of the beef-vegetable mixture into each toasted roll. Arrange 4 slices of white American cheese over the meat in each sandwich, covering as much of the filling as possible.

Cover the skillet with a lid (or tent with foil) for 1–2 minutes to melt the cheese. Alternatively, place sandwiches under a broiler for 30–60 seconds until cheese is melted and bubbly—watch carefully to prevent burning.

Open the lid, optionally spread mayonnaise or cheese whiz inside the top roll, sprinkle with chopped parsley if using, then close the sandwich and press lightly.

Cut sandwiches in half if desired and serve immediately while hot.