Plot: Hosts Bridget Lancaster and Julia Collin Davison unlock the secrets to making a Mexican staple: Crispy Tacos (Tacos Dorados) and gadget critic Lisa McManus reviews a must-have for home cooks: fire extinguishers. Science expert Dan Souza then gives a demonstration of fast-freezing liquid nitrogen, and test cook Erin McMurrer makes the perfect Roasted Poblano and Black Bean Enchiladas for Bridget