Test cook Bryan Roof hits the road to Lockhart, Texas, where he explores its barbecuing traditions, and then cooks up some Barbecued Chuck Roast for host Bridget Lancaster. Toni Tipton-Martin shares the origins of ranch dressing. And test cook Kelly Song prepares a delightful Tomatillo and Bibb Lettuce Salad with Tomatillo Ranch for host Julia Collin Davison.