Simmer the onion with 1/2 cup of the stock in a large covered non-stick saucepan for 5 minutes. Uncover and continue to cook, stirring occasionally, until the stock has reduced entirely. Transfer to a plate and set aside until required.

Add the steak to the saucepan and dry-fry until the meat is lightly browned. Return the onions to the saucepan together with the remaining stock and the red wine. Cover and simmer gently for about 1-1/2 hours, or until tender.

Preheat the oven to 375°F. Blend the flour with 3 tbsp of cold water, add to the saucepan and simmer, stirring all the time until the sauce has thickened.

Add the mushrooms and continue to cook for 3 minutes. Season to taste and spoon into a 5 cup pie dish.

Brush a sheet of filo pastry with a little of the oil, then crumple it up loosely and place oil-side up over the filling. Repeat with the remaining pastry and oil.

Bake in the oven for 25 - 30 minutes, until the pastry is golden brown and crispy. Serve with mashed potatoes and wax beans.