3. Heat oil in a frying pan and sear sides of the lamb. Allow to cool.
4. To make the sauce, put wine, balsamic, sugar, cinnamon and allspice in a small pot. Bring to a boil and reduce by half. Add stock and simmer a further 3 minutes. Mix cornflour with a little water and add to sauce. Simmer until thickened slightly.
5. In a clean bowl, beat egg whites until thick. Fold through mustard mix. Smother on the sides of the lamb, then place in a baking dish. Place in hot oven for 15-20 minutes or until lamb is cooked through and the souffle is lightly browned.