Crush the peppercorns slightly, either using a mortar and pestle or a rolling pin.
Melt the butter in a saucepan over medium high heat. Add the shallots and saute until soft, about 3 minutes. Add the brandy and boil for another 3 minutes. Add beef stock and boil another 3 minutes.
Finally, add the cream and reduce the heat to medium. Heat through, but don't allow the peppercorn sauce to boil. Once the sauce is at your desired thickness, test for seasoning. Add salt if necessary, then serve with your favourite steak.