Active: 30 minutes Total: 30 minutes

3 shallots 6 Tbsp olive oil 1 lb medium Yukon hold potatoes, sliced 1/4 in. thick 1 1/2 lb skirt steak, cut crosswise into 6 pieces Kosher salt and pepper 1 lemon 1/2 cup fresh flat-leaf parsley, finely chopped 2 tsp capers, chopped 1 clove garlic, finely chopped 1 bunch arugula, thick stems discarded

1. Heat the broiler. Line a broiler-proof rimmed baking sheet with foil. Thinly slice 2 shallots. Heat 2 Tbsp oil in a large skillet over medium heat. Add the potatoes and cook, turning occasionally, for 5 minutes. Add the sliced shallots and cook, turning the potatoes occasionally, until they are golden brown and tender, 5 to 6 minutes more. Transfer the vegetables to a plate and cover with foil to keep warm.
2. Season the steak with 1/2 tsp each salt and pepper and transfer to the prepared sheet. Broil to desired doneness, 2 to 4 minutes per side for medium-rare. Transfer to a cutting board and let rest for at least 5 minutes before slicing.
3. While the steak cooks, make the dressing: Finely chop the remaining shallot and place in a medium bowl. Finely grate 2 tsp lemon zest into the bowl, then squeeze in 2 Tbsp of juice.
4. Stir in the parsley, capers, garlic and 1/4 tsp each salt and pepper. Gradually whisk in the remaining 4 Tbsp oil. Arrange the arugula, steak and vegetables on a platter. Drizzle with dressing.