In a small bowl, combine the olive oil, chipotle peppers, garlic, cumin, smoked paprika, oregano, salt, and pepper
Rub the marinade all over the flank steak, making sure to coat all sides.
Placethe steak in the refrigerator and let it marinate for at least 2 hours, orovernight.
When ready to cook, preheat the grill to medium-high heat.
Grill the steak for 10-12 minutes, flipping once, until it reaches an internal temperature of 135°F (for medium-rare).
Let the steak rest for 5 minutes before slicing.
Slice the steak against the grain and serve.