Seared Steak with Spicy Rice Noodles

1. 1Place all of the ingredients in a medium, nonreactive bowl and whisk to combine; set aside.

For the noodles and steak:

1. 1Line a baking sheet with a layer of paper towels; set aside. Bring a medium saucepan of water to a boil over high heat. Add the bok choy and boil until crisp-tender, about 1 minute. Remove with a slotted spoon to the prepared baking sheet; set aside.
2. 2Return the saucepan of water to a boil. Place the noodles in a large, heatproof bowl and pour the boiling water over them. Stir briefly to separate the noodles, then let them soak until they’re loose and pliable, about 5 minutes. Drain in a colander; set aside.
3. 3Rub the oil on both sides of the steak and season the meat generously with salt and pepper. Heat a large frying pan over medium-high heat until hot, about 3 minutes. Carefully lay the steak in the pan and sear for 6 minutes per side for medium rare. Transfer to a cutting board to rest, about 5 to 10 minutes.
4. 4Return the noodles to the large bowl and add the reserved bok choy. When the flank steak is ready, slice it lengthwise with the grain into 3 strips. Slice each strip against the grain into 1/8- to 1/4-inch-thick pieces and add to the bowl. Give the reserved vinaigrette a quick whisk, then pour it over the steak, noodles, and bok choy. Add the cilantro and toss, using tongs, until everything’s evenly combined and coated. Serve garnished with peanuts and lime wedges.