Heat the oil or lard in a large heavy skillet over medium heat. When very hot, pat the steak dry, sprinkle with salt and lay in the pan in a single layer. Sear well on both sides until meat is rare to medium rare, 3 to 4 minutes. Remove to rack set over a plate. Add the onions to the skillet and cook, stirring regularly, until brown but still crunchy, about 5 minutes. Add the salsa to the skillet along with the cumin, pepper, and remaining cloves of garlic. Stir as the salsa reduces for several minutes, then stir in the broth and simmer for about 5 minutes. Return the meat to the pan and let it warm through, about 5 minutes or until the meat is done to your liking. Taste the sauce and add a little more salt and sugar if necessary. With a spatula or slotted spoon, transfer the steaks to a serving platter, then spoon the sauce, onions and garlic over and around them. Sprinkle with the cilantro.