Preparation

• Pat the steak dry, and season with 1-1/4 tsp. salt and 1/2 tsp. pepper.
• Put a large, heavy-based stainless-steel skillet over medium-high heat for 1-1/2 minutes (it’s ready when a droplet of water instantly evaporates upon hitting the surface). Add 2 Tbs. of the oil. Once it’s shimmering hot, about 30 seconds, carefully add the steaks, evenly spaced.
• 煎牛排,原状,直到布朗在the edges and a corner easily pulls up when lifted with tongs, about 3 minutes. Flip and cook the other side until medium rare, 2 to 3 minutes more; if checked with an instant-read thermometer, a thicker piece will register 130°F to 140°F and the steak will be bright pink when sliced. Transfer to a cutting board, and tent with foil. Rest for at least 10 minutes while you make the sauce.
• Return the skillet to the stovetop, and lower the heat to medium. Add the apple, shallots, and remaining 1 Tbs. of the oil, sprinkle with 1/4 tsp. salt, and cook, stirring occasionally and scraping the bottom of the pan with a wooden spoon to incorporate any brown bits, until the shallot softens and browns lightly, about 2 minutes.
• Raise the heat to high, and add the broth. Cook, stirring and continuing to scrape up any remaining browned bits, until the broth reduces by about half, about 3 minutes. Add the mustard and cream, and cook, stirring, until the mixture thickens, about 1 minute. Add the tarragon, and season to taste with salt and pepper. Spoon over the steak and serve immediately.