Turn the oven to fan 180c, gas 6.

Heat half the oil in a frying pan on a high heat and cook the venison for about 30 seconds to 1 minute on each side, until browned. Transfer to a baking tray and cook in the oven for about 5mins for rare, 8 mins for medium or 10-12 mins for well done. Leave to rest under foil while you make the sauce.

SAUCE

Meanwhile, add the rest of the oil to the pan you cooked the venison in and fry the onions and mushrooms for 3-4 minutes until soft. Add the wine and stock and bubble of a high heat for a few minutes until thickened. Remove from the heat and add the butter, chocolate, a little salt and a really god grinding of black pepper, then stir until melted