Philly-Style Mushroom Cheesesteak

Melt the cheese right over the warm mushrooms, onions, and sliced steak in the pan by covering the skillet with a lid or foil. If you like the cheese to be browned, run the whole open-faced sandwich under the broiler.

• 1 Tbs. canola oil; more if needed
• 9 oz. New York strip steak, 1 inch thick
• 1/2 tsp. coarse salt; more to taste
• Scant 1/4 tsp. freshly ground black pepper; more to taste
• 8 medium cremini or button mushrooms (5 to 6 oz. total), thinly sliced
• 1/2 medium yellow onion (2 to 3 oz.), thinly sliced
• 2 medium scallions (white and green parts), thinly sliced on a sharp angle (about 1/4-cup)
• 1 tsp. minced garlic
• 6 small cherry tomatoes (or grape tomatoes), quartered
• 2 thin slices provolone or fontina cheese (about 1 oz. each)
• 2 slices bread (about 1/2-inch thick), cut from a round country loaf or other rustic loaf, lightly toasted

Heat the oil in a 10-inch heavy skillet (preferably cast iron) over medium-high heat until very hot but not smoking. Season the steak on both sides with the salt-and pepper. Put the steak in the hot oil and sear for 3 minutes. Turn the steak and cook for another 2 minutes (it will be very rare but will cook more later). Take the skillet off the heat, transfer the steak to a cutting board, and cover loosely with foil.

Return the skillet to medium heat. Add the mushrooms and onion and cook, stirring occasionally, until they’re tender and beginning to brown, about 5 minutes. Add another 1 Tbs. canola oil if the pan seems dry. Add the scallions and garlic and cook until the scallions are limp, about 1 more minute. Loosely cover the skillet and slide it off the heat.

Trim the fat from the side of the steak and cut the steak into thin (1/8- to 1/4-inch) slices. Add the steak slices, any accumulated juices, and the tomatoes to the mushrooms in the pan; season with salt and pepper and toss well. Divide into two loose piles in the skillet. Lay a cheese slice over each pile; cover the skillet to melt the cheese (briefly set the skillet over low heat, if necessary). Slide a large metal spatula under one pile of steak, mushrooms, and cheese and drape it over the toasted bread; repeat with the other pile. Serve immediately.