01 - Remove steaks from the refrigerator 30 minutes before cooking to bring to room temperature. Pat dry thoroughly with paper towels and season both sides generously with salt and black pepper.
02 - Heat olive oil in a heavy skillet over medium-high heat until shimmering. Add steaks and sear for 3-4 minutes per side for medium-rare doneness. Adjust timing slightly for more or less doneness as desired. Transfer steaks to a plate, tent loosely with foil, and let rest.
03 - Reduce heat to medium. Add butter to the same skillet and sauté the minced shallot for 1-2 minutes until softened and translucent, scraping up browned bits from the bottom.
04 - Stir in crushed green peppercorns. Carefully pour in brandy or cognac and let bubble for 30 seconds, continuing to scrape up any fond from the pan bottom.
05 - Pour in beef stock and simmer for 2 minutes until slightly reduced and concentrated.
06 - Lower heat and stir in heavy cream. Simmer gently for 2-3 minutes until sauce thickens enough to coat the back of a spoon. Season with salt to taste.
07 - Return rested steaks to the pan for 1 minute, spooning warm sauce over them to reheat. Transfer to plates and serve topped with generous spoonfuls of peppercorn sauce.