Nacho Cheese Doritos Locos Tacos has been one of the biggest new menu items in recent times, with Taco Bell selling more than 300 million of the tacos with flavored shells since their introduction in March.

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Additionally, Taco Bell has found great success over the past year with new menu items, highlighted by its incredibly successful Doritos Locos Tacos and its new, higher-end Cantina Bell menu.

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Taco Bell Grille was an experimental restaurant the company opened in Garden Grove, California to test higher-end menu items, such as smoothies.

FORBES: Companies & Strategies

Taco Bell Grille was an experimental restaurant the company opened in Garden Grove, Calif. to test higher-end menu items, such as smoothies.

FORBES: Marketing