Season both sides of the steaks with some salt, then sprinkle one side of the steaks with the coarsely ground pepper and press it in with your fingers.
Preheat a large skillet over medium-high heat with 2 tablespoons of EVOO, two turns of the pan. Add the steaks peppered side down and cook them for 4 minutes. Turn over and cook 3 minutes more for medium-rare -- cook a minute longer on each side for medium to medium-well. Remove steaks to a plate and cover loosely with aluminum foil to keep them warm while they rest.
Return the skillet to the heat with a drizzle more of EVOO if necessary, add the onion, garlic and a little salt. Cook, stirring frequently, for 3-4 minutes. Remove skillet from heat, add the cognac then return it to the burner and let it flame up.