Seal the sirloin all over including the ends. Set aside in the roasting tin. Preheat the oven to 220C/200C Fan/Gas 7. Meanwhile mix together the mustard, salt and pepper and rub all over the sirloin.
Yorkshire puddings make the perfect wrap for rare sirloin steak and onion gravy ... keeping the cooked wraps warm in a very low oven. To cook the steak, mix the mustard powder, peppercorns ...