Ingredients

  • 6 tablespoons canola oil
  • 3 medium Spanish onions1 thinly sliced, 2 cut into thin wedges attached at the root end
  • 3 garlic cloves, thinly sliced
  • 2 shallots, thinly sliced
  • 1/3 cup minced fresh rosemary
  • 2 tablespoons red wine vinegar
  • 1 teaspoon ground cumin
  • 1/2 teaspoon cayenne pepper
  • 1 3/4 pounds trimmed flank steak
  • 2 pounds small unpeeled new potatoes, quartered
  • 2 tablespoons balsamic vinegar
  • 1 tablespoon olive oil
  • Salt and freshly ground pepper

Method

  • Heat the canola oil in a large nonreactive skillet.
  • Add the sliced onion, garlic and shallots and cook over moderately low heat, stirring, until softened, about 5 minutes.
  • Add the rosemary and cook for 1 minute.
  • Add the red wine vinegar, cumin and cayenne pepper and let cool.
  • Scrape the marinade into a large, sturdy resealable plastic bag.
  • Add the flank steak and spread the marinade over it.
  • Seal the bag and refrigerate for 1 to 4 hours, turning the bag twice.
  • Preheat the oven to 400.
  • In a large bowl, gently toss the potatoes, onion wedges, balsamic vinegar and olive oil and season lightly with salt and pepper.
  • Spread the vegetables in a large nonstick roasting pan and roast for about 40 minutes, stirring once, until tender and browned.
  • Light a grill or heat a large cast-iron grill pan.
  • Scrape the marinade off the steak.
  • Grill the steak over moderately high heat for about 15 minutes, turning once, until browned and medium-rare.
  • Cover with foil and let rest for 5 minutes.
  • Season the meat with salt and pepper.
  • Thinly slice the steak across the grain and serve with the roast potatoes and onion wedges.