- One 1 3/4-pound flank steak
- 1 tablespoon Dijon mustard
- 1/4 cup dry red wine
- 1/4 cup pure olive oil
- 4 large garlic cloves
- 1/2 teaspoon finely chopped thyme
- 1/2 cup mayonnaise
- 1 teaspoon fresh lemon juice
- Salt and freshly ground pepper
- 8 rosemary focaccia or other rolls, split
- 1/2 pound sliced imported provolone or Fontina cheese
- 8 lettuce leaves
- Brush the flank steak on both sides with the mustard. Put the steak in a sturdy resealable plastic bag and add the wine. Seal the bag, pressing out any air, and refrigerate overnight. Drain the steak, pat dry and bring to room temperature before grilling.
- Meanwhile, in a small saucepan, combine the olive oil and garlic and cook over low heat until the garlic is golden and soft, about 15 minutes. Using a slotted spoon, transfer the garlic to a small bowl; reserve the garlic oil. Add the thyme to the garlic and mash to a paste. Stir in the mayonnaise and lemon juice and season with salt and pepper.
- Light a charcoal grill or preheat a cast-iron grill pan. Brush the steak with the reserved garlic oil, season liberally with salt and pepper and grill over moderate heat for about 15 minutes, turning once, for medium-rare meat. Transfer the steak to a cutting board to rest for 5 minutes. Thinly slice the meat across the grain on the diagonal.
- Spread the garlic mayonnaise on the rolls and top with the flank steak, cheese and lettuce. Cut the sandwiches in half and serve.
The sandwiches can be made 6 hours ahead.