With clean hands and a clean cutting board, we smash the garlic cloves with the side of a knife (carefully) and discard the peels. We sprinkle the cloves of garlic with salt and mince to a paste. We add this to a ramekin, along with the chile powder, brown sugar, smoked paprika, cumin, a pinch of salt and black pepper, and the espresso powder. We stir well.
In a resealable storage bag, we place the steak and pour in half the rub. We smoosh it all over one side of the steak, and then pour the remaining half of the rub onto the other side of the steak. We spread it as best we can and then seal the bag shut. After washing our hands, we place the bag on a dinner plate and refrigerate for a couple of hours since we have the time. We could have also left it at room temperature if we were going to cook it within the hour.
We remove the bag from the refrigerator 30 minutes before we are ready to cook it.
We heat our sauté pan for a few minutes on medium heat. We add the oil to the hot pan, remove the steak from the bag, and add it carefully to the oil.
We cook the steak for about 5 minutes on each side. After that, we remove the steak to a clean plate and check the temperature with our digital meat thermometer. It reads 130° F, which corresponds to medium-rare, at the thickest part.
We let the steak rest for a few minutes to seal in the juices.
We cut the steak against the grain, somewhat on an angle to get nice slices. We serve it with tortillas in a Mexican-inspired meal.