Steak Sandwiches

Ingredients

• 1 lb skirt steak
• 1 1/2 tsp ground pepper
• 1/2 tsp salt, divided
• 2 tbsp canola oil or other neutral oil, divided
• 1 cup sliced yellow onion
• 8 oz sliced cremini mushrooms
• 1/2 cup nonfat plain yogurt
• 1/4 cup light garlic-and-herb spreadable cheese (such as Boursin)
• 1 tbsp stone-ground mustard
• 1 tbsp prepared horseradish
• 2 (12-inch) whole-grain hoagie or Italian rolls
• 2 cup baby arugula

Instructions

1. Season steak all over with pepper and 1/4 teaspoon salt. Cut the steak into 2 or 3 pieces to fit in a single layer in a large cast-iron skillet.
2. Heat 1 tablespoon oil in the skillet over high heat until shimmering. Add the steak, in batches if necessary to prevent overcrowding; cook, undisturbed, until charred and well browned on bottom, about 2 minutes. Flip and cook until a thermometer inserted in the thickest portion registers 125° to 130°F for medium, about 2 minutes. Transfer to a cutting board and let rest for 10 minutes before thinly slicing across the grain. Do not wipe the pan.
3. Heat the remaining 1 tablespoon oil in the pan over medium-high heat. Add onion, mushrooms and the remaining 1/4 teaspoon salt; cook, stirring occasionally, until softened and charred, about 8 minutes. Remove from heat.
4. Whisk yogurt, cheese, mustard and horseradish together in a medium bowl until combined. Split rolls in half horizontally and tear out some of the inner bread to create a 1/2-inch-deep cavity inside each roll. Spread the cheese mixture evenly on the cut sides of each roll.
5. Place 1 cup arugula on the bottom of each roll; top each with 2/3 cup vegetable mixture, about 7 ounces sliced steak and the roll tops. Cut each roll in half. Serve immediately.