500g cold boiled or roast beef
a knob of butter or two tablespoons olive oil
250g finely-chopped onions
1 tablespoon flour
half a mugful of beef stock (if you use boiled beef for this recipe, you should have some stock to hand)
half teaspoon salt
freshly-ground black pepper
I tablespoon red wine vinegar - tarragon-flavoured is best
2 tablespoons of chopped cornichons and capers
fresh bread crumbs
heat knob of butter (or the olive oil, or a mixture of the two) in a frying pan. Add onions and cook until slightly browned. Sprinkle with flour and cook, stirring constantly, until the flour starts going brown. Be careful not to let it burn or you'll have to start all over again!
stir in stock, salt, pepper, and vinegar, squashing out any lumps of flour that may form. Bring sauce to the boil, then turn down heat, cover and simmer gently for about 25 minutes. I add chopped cornichons and capers to this sauce, but this is certainly not classical!
cut the beef into thin slices. Arrange in a fireproof flat dish. Pour sauce over the meat, then sprinkle with breadcrumbs which you dot with butter to stop them from burning. Bake at 230C degrees for about ten minutes, until the breadcrumb topping is nicely golden brown.