Taco Bell's new vegetarian menu includes 13 A.V.A.-certified menu items, including a 7-Layer Burrito and Cantina Power Veggie Bowl.

IRVINE, CALIF. — Taco Bell, a subsidiary of Yum! Brands Inc., has become the first quick-service restaurant chain to offer menu items certified by the American Vegetarian Association (A.V.A.). The move is part of Taco Bell’s initiative to provide customers with choice, transparency and simplicity. Earlier this year, Taco Bell unveiled plans to remove all artificial flavors and colors from its food and replace them with alternatives perceived as natural by the end of 2015. The company also has set a goal for 2017 to remove all artificial preservatives and additives.

Brian Niccol, c.e.o. of Taco Bell

“At Taco Bell, vegetarians are not an afterthought,” said Brian Niccol, chief executive officer of Taco Bell. “We sell more than 350 million vegetarian menu items each year, but until now haven’t been vocal about it. The recent launch of ta.co, which makes customization easy, made this the perfect time to move our vegetarian menu from the background to the forefront to further illustrate our commitment to delivering food that fits our customers’ evolving lifestyles.”

Taco Bell said its vegetarian menu offers 13 A.V.A.-certified menu items, including a 7-Layer Burrito and Cantina Power Veggie Bowl. The Q.S.R. offers 35 A.V.A.-certified vegetarian ingredients (26 of which are also vegan), and beans are available to substitute for meat to create one of millions of different possible vegetable-friendly combinations.

Earlier this week, Taco Bell unveiled a new and improved web site at ta.co. Visitors to the site may customize menu items quicker than before and order food ahead of time. Other features include the ability to re-order customized items and the chance to select favorite foods for the future. Customers also will have access to exclusive discounts and other perks.

“We get it — being a vegetarian can be tough when you go out to eat,” Mr. Niccol said. “We’re proud to treat meat lovers and vegetarians equally — equally delicious, equally craveable and equally affordable.”