Ingredients

  • 1 flank steak (about 1 pound 10 ounces)
  • Kosher salt and freshly ground black pepper
  • 1 fresh poblano chile
  • 1 Fresno chile or red jalapeno
  • 1 medium onion, sliced into 1/4"-thick rounds
  • 4 tablespoons vegetable oil, divided
  • 3 cups (packed) frisee
  • 3 tablespoons balsamic vinegar
  • 2 teaspoons honey

Method

  • Preheat broiler. Line a rimmed baking sheet with foil. Season steak with salt and pepper; set aside.
  • Place chiles and onion on prepared sheet and brush with 2 tablespoons oil. Broil vegetables, turning once, until charred and soft, about 8 minutes. Transfer chiles and onion to a medium bowl and cover with plastic wrap. Let vegetables steam in covered bowl for 10 minutes.
  • Meanwhile, line a platter with the frisee. Heat remaining 2 tablespoons oil in a large cast-iron or other heavy skillet over medium-high heat. Add steak to skillet and cook, turning once, until browned and cooked to desired doneness, about 10 minutes for medium-rare. Transfer steak to frisee-lined platter; let rest. The heat from the steak will wilt the greens slightly.
  • Peel chiles. Cut in half and remove seeds; cut out core. Finely chop chiles and onion and transfer to a small bowl. Add vinegar and honey to chiles and stir to coat well. Season salsa to taste with salt.
  • Transfer steak to a work surface and thinly slice crosswise against the grain. Return sliced steak to platter, arranging over wilted frisee, and spoon charred pepper salsa over.