Braised Short Ribs

canola oil

flanken-style short ribs with bones, cut 2 inches thick (about 4 pounds); see Note

Kosher salt and freshly ground pepper

large onion, finely chopped

carrots, sliced

celery ribs, sliced

garlic cloves, thickly sliced

bottle dry red wine, such as Cabernet Sauvignon

thyme sprigs

chicken stock