Make a horizontal cut into the side of each steak to create a pocket and insert the Peppadew peppers.
Press the cracked peppercorns into both sides of the steak.
Heat a frying pan over a high heat and add the butter and oil. When the butter is foaming, add the steak and cook for two minutes on each side, or until cooked to your liking. Remove the meat and set aside on a plate to rest in a warm place.
Reduce the heat to medium and add the brandy to the frying pan. Carefully light the brandy and flambé. When the flames have died out, scrape up all the meat juices with a wooden spoon.
Add the mustard, Worcestershire sauce, beef stock and red wine and whisk to combine. Cook until the sauce has thickened and reduced in volume by a third.
Pour any juices that have seeped from the steaks into the sauce and stir.
Add the green peppercorns and cream and cook for a further two minutes. Season, to taste, with salt.
Place the steak back into the frying pan with the sauce to warm the meat through. Do not boil the sauce.
Remove the steak and place onto a plate. Drizzle over the sauce and serve with chips or new potatoes and a watercress salad.