To make this lean cut of beef tender, three steps are needed: a long marination, a fast grilling, and slicing against the grain—in the opposite direction of its meat fibers.
Ingredients
For the steak:
- 2 tablespoons extra virgin olive oil
- 2 tablespoons red wine vinegar
- 1/2 teaspoon coarse salt (kosher or sea)
- 1/2 teaspoon freshly ground black pepper
- 2 garlic cloves, peeled and minced
- 2 pounds flank steak or hanger steak
For the chimichurri:
- 1 bunch fresh flat-leaf parsley, rinsed, shaken dry, and trimmed (keep on the top half of the stems)
- 1/2 bunch fresh cilantro, rinsed, shaken dry, and trimmed (keep on the top half of the stems)
- 3 to 4 cloves garlic, peeled and coarsely chopped
- 1 tablespoon fresh or 1 teaspoon dried oregano
- 1 teaspoon merquén or hot red pepper flakes
- 1/2 cup extra virgin olive oil
- 3 to 4 tablespoons red wine vinegar
- 3 to 4 tablespoons cold water
- Coarse sea salt
- Freshly ground black pepper
- 1 avocado, peeled, pitted, and diced
Directions
Step 1
Make the marinade: Whisk together the olive oil, vinegar, salt, pepper, and garlic. Place the steak in a glass baking dish that will hold it and pour on the marinade, flipping the meat to coat both sides. Cover and place in the fridge for four hours or up to overnight.
Step 2
Two hours before serving, make the chimichurri: Place the parsley, cilantro, garlic, oregano, and merquén in a food processor and finely chop, running the machine in short bursts. With the motor running, add the olive oil in a thin stream, followed by 3 tablespoons vinegar and 3 tablespoons of water. Taste the chimichurri, adding another tablespoon of vinegar if you want it more tart and, if necessary, another tablespoon of water for a pourable consistency. Season with salt and pepper to taste; it should be highly seasoned. Set aside. Fold in the avocado chunks just before serving.
Step 3
Preheat your grill to medium-high. Remove the steak from the marinade and pat dry. Grill for 3 to 5 minutes per side, depending on thickness—it’s best medium-rare. Let the meat rest for 2 to 3 minutes, then thinly slice on the diagonal. Arrange on a platter and serve with the avocado chimichurri.
Serves 4 to 6