Heat the oil in a large non-stick frying or griddle pan, season the steaks, brush with oil on both sides and cook according to your preference. Transfer to warm serving plates and cover loosely with foil to keep warm.
Reduce the heat under the pan and add the mushrooms and garlic. Cook for 3 minutes, stirring occasionally. Add the stock, increase the heat and boil for 3 minutes until slightly reduced. Add the whisky and cream and reduce a further 3-4 minutes until the sauce is slightly thickened. Stir in the chives.
Serve the steaks with the sauce and seasonal vegetables.