Step aside, sesame-seed bun. Take a seat, Texas toast.

The top growing bread on restaurant menus offer a twist on tradition, adding texture and excitement to standard sandwiches. With Old World inspiration and artisanal appeal, pretzel bread, brioche and flatbreads are on the rise.

“Q.S.R. and fast-casual operators are looking to make standard items seem more interesting and unique and trying to create more competitive positioning of items without revamping the whole menu,” says Maeve Webster, senior researcher at Datassential. “Changing the carrier is a fairly easy change compared to other changes you could make. It’s not necessarily disruptive to the back of the house from a cost or handling standpoint. And you can increase the price point because it has a more unique, artisan perception.”

The top growing bread between 2008 and 2012 was pretzel bread, rising at a rate of more than 79%, according to Datassential’s US Chains & Independents MenuTrends Database, which tracks appetizers and entrees across all food service segments. Brioche climbed nearly 75%, and flatbread grew 61% during the period.

No longer limited to ballgame bleachers and neighborhood delis, pretzel bread is popping up on mainstream menus as soft-baked sticks, bagels, frankfurter rolls and burger buns. TGI Fridays in April launched a small-plates menu with beef and Swiss sliders on pretzel rolls, and Blimpie unveiled a turkey sub on pretzel bread that will be available nationally in June. Wendy’s began testing a bacon cheeseburger on a pretzel bun in select markets at the beginning of the year.

“The pretzel bun is a real natural because it brings a lot of these cues of Old World to an already recognizable item,” says Kara Nielsen, a trend researcher at San Francisco-based CCD Innovation. “It has a deeper, darker flavor, and it has a little artisanal touch to it, even if it’s a manufactured product.”

Similarly, brioche adds an indulgent texture and premium touch to a basic B.L.T.

“It has a very rich look and flavor profile that is appealing and lends a premium perception to an overall item,” Webster says. “You see brioche experiencing strong growth during the breakfast daypart, not only as a carrier for sandwiches, but also for other applications such as french toast.”

In April, IHOP debuted three varieties of brioche french toast, joining the likes of Perkin’s Restaurant, Mimi’s Cafe and Corner Bakery, who each added brioche french toast items last year.

The rich, flaky bread is featured on dinner and dessert menus, too. Such chains as TGI Fridays and The Cheesecake Factory serve barbecue pulled pork and burgers on brioche buns, and Carrabba’s Italian Grill’s limited-time items last year included a Nutella- and banana-filled panini and a Limoncello-drizzled bread pudding, both made with brioche.

“More and more operators are trying to get every single ingredient to work for them across as many applications and platforms as they can,” Webster says. “Bread can be a carrier for hamburgers and sandwiches or used to create dip-style appetizers. It’s a kitchen workhorse.”

Such a versatile carrier is flatbread, which has rolled out recently in sandwiches, alongside dips or grilled with toppings.

“There are so many different variations of flatbread, from your extremely paper-thin lavash all the way to a thin-crust pizza flatbread,” Webster says. “It can be extremely versatile and work across dayparts.”

Tim Hortons last year added flatbread breakfast paninis with sausage or bacon, egg and cheese. This spring, Wendy’s launched grilled chicken sandwiches served on multigrain flatbread made with flax seeds, cracked wheat, rolled oats, millet and sesame seeds.

“Flatbread benefits from a perceived healthfulness,” Webster says. “They suggest fewer carbs, less heavy. Flatbread has a better-for-you halo.”

As grilled appetizers, this year’s introductions include a Tuscan chicken flatbread with marinara sauce and peppers from Fazoli’s, a California grilled chicken flatbread with avocado and pico de gallo from Chili’s Grill and Bar, and a springtime flatbread with asparagus, mushrooms and bacon from Noodles and Company.

This style of flatbread bubbles up from the recent artisan pizza movement as well as a trend toward more casual dining, Nielsen says.

“It’s a great shareable appetizer,” she says. “You can offer it both with a variety of vegetarian and savory meat toppings. And because it’s flatbread and not pizza, you can get really creative and make a flatbread that suits the brand, whether it’s a slightly more healthful one or a slightly more decadent one.”

While tried-and-true wheat bread and wraps remain most popular on menus, according to Datassential, restaurants continue to experiment with the sandwich’s shell. Dunkin’ Donuts tested a bacon and egg sandwich on a glazed donut bun this year, and Taco Bell is toying with a sausage and egg “taco” packed in a folded waffle.

“In the food service sector, they’re always looking to bring news to the sandwich space,” Nielsen says. “There’s a continual quest for the next ciabatta.”

Nielsen says she expects to see more sprouted bread and ryes emerging as an extension of Old World-inspired fare.

“We’re seeing more European and Scandinavian seedy, nutty breads and some breads made with sprouted grains, and marble rye bread,” she says. “I think rye bread will eventually get a little bit of a renaissance.”