- 1 tablespoon extra-virgin olive oil
- 1 small yellow onion, finely chopped
- 1 garlic clove, finely chopped
- 1 tablespoon prepared chili powder
- 1 teaspoon ground cumin
- 1/2 teaspoon paprika
- 1/2 cup ketchup-style chili sauce
- 1/2 cup drip-brewed espresso or dark roast coffee
- 2 tablespoons packed light brown sugar
- 2 tablespoons balsamic vinegar
- 1 1/2 teaspoons kosher salt
- 1 teaspoon prepared chili powder
- 1/2 teaspoon ground cumin
- 1/2 teaspoon freshly ground black pepper
- 1 flank steak, about 1 1/2-pounds and 3/4-inch thick
- 1/4 cup (½ stick) salted butter, softened
- 2 garlic cloves, minced
- 4 slices white, French or Italian bread, each about 1-inch thick
- 2 cups baby arugula
- extra-virgin olive oil
In a heavy, medium saucepan over medium-low heat, warm the oil. Add the onion and cook until super soft and very dark, about 30 minutes, stirring occasionally. Stir in the garlic and cook until fragrant, about 1 minute. Add the chili powder, cumin and paprika and stir well. Add the remaining sauce ingredients and bring to a boil over medium-high heat. Reduce the heat to low and simmer, uncovered, until the sauce thickens and is reduced to about 1 cup, 15 to 20 minutes, stirring occasionally. Soak the wood chips in water for at least 30 minutes.
Mix the rub ingredients. Lightly brush the steak on both sides with oil and season evenly with the rub. Allow the steak to stand at room temperature for 15 to 30 minutes before grilling. COMBINE the butter and garlic, and then spread on both sides of the bread slices. Stand the slices upright, cut sides together, on a plate until ready to grill.
Prepare the grill for direct cooking over medium heat (350° to 450°F).
Drain and add the wood chips to the charcoal or to the smoker box of a gas grill, following manufacturer’s instructions, and close the lid. When smoke appears, grill the steak over direct medium heat, with the lid closed, until cooked to your desired doneness, 8 to 10 minutes for medium rare, turning once. During the last minute of grilling time, brush the steak on both sides with some of the sauce, and turn once or twice to glaze the steak. Remove from the grill and let rest for 3 to 5 minutes.
Grill the bread slices over direct medium heat until lightly toasted, about 1 minute, turning once.
Cut the steak across the grain into thin slices. Build the sandwiches on the toasted bread with arugula, steak and sauce. Drizzle the sandwiches with the carving juices. Serve warm with additional sauce on the side. Any leftover sauce can be stored in the refrigerator in a covered container for up to two weeks