Heat a pan until smoking hot. Brush with a little oil.
Place the beef steaks on the pan. Cook for about 2-3 minutes on each side, depending on how you like your beef cooked.
Remove the beef from the pan when it is sealed on both sides. Transfer to a warm plate. (Popping the steaks into a preheated oven for 5-10 minutes at this stage will give you a well done steak).
Meanwhile quickly make up the sauce. Heat a deep based pan with a little butter and then add the crushed garlic, sliced shallots and mixed mushrooms. Cook gently until they are all softened down.
Remove pan from heat, add in the whiskey and allow to bubble up a little. Return pan to heat.
Next pour in the cream and the beef stock and allow the entire mixture to come to the boil for 5-6 minutes. Continue to simmer for approximately 6-7 minutes and then season as required.
Scatter in the snipped chives. Serve immediately with the pan seared fillet of beef.