In a frying pan, melt the butter and fry the shallots, garlic over a medium heat, until softened.
Add the thyme, peppercorns and brandy, tilt the pan towards the flame and set the brandy alight (if you're not comfortable with this, cook for around 3 mins to burn the alcohol off).
Add the stock and cream, gently simmer for around another 5mins and serve, drizzled over steak.