For this killer make-ahead party dish, master butcher Rob Levitt of The Butcher & Larder in Chicago braises a large bone-in beef shank—a tough, wintry cut—until it's fork-tender. Levitt finishes the meat on the grill for an extra layer of smoky flavor. Slideshow: More Taco Recipes
The braised shank can be refrigerated in the braising liquid in the casserole for up to 4 days. Rewarm gently over moderately low heat, covered, before proceeding. The pickled red onion can be refrigerated for up to 2 weeks.