Beef and Mushroom Stew

Peel and finely chop the onions. Clean and thinly slice the mushrooms. Cut the gherkins into sticks lengthwise, then into thin strips. Cut the meat first into slices 1 cm thick, then into strips 1 cm wide. Heat the oil in a frying pan and saute the meat over a high heat for 2 minutes. (You may need to do this in batches) Take out the pan and keep warm. Pour off the frying fat and add the butter to the pan. Sweat the onions and mushrooms in the butter, then dust with flour, add the stock and briefly bring to the boil. Stir in the sour cream and cook, stirring, until the sauce is reduced and creamy. Mix the meat, mustard and gherkins into the sauce, season with salt and pepper and add the lemon juice. Serve in bowls garnished with parsley. Boiled potatoes tossed in butter go well with this dish.