Taco Bell kitchen delivers deep-fried chicken taco shell, testing a Cheetos burrito and bagged nachos

The heart of Taco Bell’s operation is innovating the humble taco. Over 54 years, the chain’s Mexican-inspired menu has evolved from fried-to-order taco shells to pillowy gorditas to Doritos Locos Tacos. This year brought the Quesalupa, a taco...