With St. Patrick's Day this weekend, it's time to get our Irish on! 2 celery stalks, cut into 3-inch pieces 3 carrots, cut into 3-inch pieces 1 small yellow onion, cut into 1-inch wedges (root end left intact) Onions Yellow/ Brown 1/2 pound small potatoes, halved if large 6 sprigs thyme 1 corned beef brisket (about 3 pounds), plus pickling spice packet or 1 tablespoon pickling spice 1/2 head Savoy cabbage, cut into 1 1/2-inch wedges Grainy mustard, for serving   In a 5-to-6-quart slow cooker, place celery, carrots, onion, potatoes, and thyme. Place corned beef, fat side up, on[...]