To make the steak: Whisk together the olive oil, lime juice, garlic, salt, and a few grinds of pepper in a large bowl. Add the steak, toss to coat, cover, and refrigerate for at least 2 hours or overnight.
To make the cilantro-lime ghee: Combine all the ingredients in a small bowl. Mash with a fork until well mixed, then refrigerate until needed.
Take the steak out of the refrigerator 45 minutes before you plan to cook it. Preheat an outdoor grill (or a George Foreman if you’re an apartment dweller). Pat the steak dry, brush off the garlic pieces so they won’t burn, and discard the marinade. Grill the steak for 2 minutes per side for medium, or until it reaches your desired level of doneness.
Transfer the steak to a plate, tent it with foil, and let it rest for 5 minutes (or 10 if you can stand it). Slice on the diagonal into 1⁄2-inch-wide strips, top with the cilantro- lime ghee, and serve with lime wedges.