Sweet & Sour Brisket with Horseradish Mousse

When I first cooked brisket (boned), it was because it was all I could afford for a pot roast. I knew already that the little triumvirate of onion, celery and carrot would make for great flavour, but uncovering the dish, I marvelled at the change wrought in the meat by slow cooking; how the connective tissues had dissolved into succulent gelatin! The dish was not pretty – it was ugly delicious! A wondrous rite of passage! The barbecue-y brisket that follows is easy to prepare, dependable an