Ingredients

  • 1 pound hanger, skirt, or flank steak
  • 1 teaspoon kosher salt plus more
  • Freshly ground black pepper
  • 1 medium tomato (about 6 ounces), halved
  • 1 tablespoon minced shallot
  • 1 tablespoon red wine vinegar
  • 1/4 cup plus 5 teaspoons olive oil, divided
  • 4 spring onions or 6 scallions, bulbs halved, dark-green parts discarded
  • 5 1/2-inch-thick slices ciabatta
  • 8 cups mixed summer lettuces (such as mizuna, baby mustard greens, and tatsoi)
  • 3/4 cup fresh basil leaves, torn into 1/2-inch-strips

Method

  • Season steak with 1 teaspoon salt and pepper; set aside. Grate cut sides of tomato on coarse holes of a box grater into a medium bowl down to the skin; discard skin. Add shallot and vinegar; whisk in 1/4 cup oil. Season to taste with salt and pepper. Set aside. DO AHEAD:
  • Build a medium-hot fire in a charcoal grill, or heat a gas grill to high. Toss spring onions in a medium bowl with 1 teaspoon oil and season with salt and pepper. Grill onions until just tender, 2-3 minutes per side. Transfer to a cutting board and cut into 2" pieces.
  • Grill steak until seared and cooked to desired doneness, 3-5 minutes per side for medium-rare, depending on steak's thickness. Transfer to a cutting board. Let rest, about 10 minutes.
  • Meanwhile, make croutons: Brush both sides of bread slices with remaining 4 teaspoons oil and season with salt and pepper. Grill bread until dark golden brown and nicely charred in spots, about 2 minutes per side. Set toast aside until cool enough to handle, then break toast into roughly 1" pieces.
  • Thinly slice steak against the grain. Toss lettuces, basil, spring onions, croutons, and some of the vinaigrette in a large bowl. Season to taste with salt and pepper. Add steak and toss gently to coat. Serve with remaining vinaigrette alongside.