Lent is a boon for business at seafood restaurants as Catholic customers look for nonmeat options for Friday dining. But for quick-service restaurants with core menu items that are primarily red meats, Lent can be a challenge.

Some quick serves, however, are starting to see the season—between February 22 and April 5 this year—as an opportunity to innovate their menus.

The now iconic story of the invention of McDonald’s fish sandwich is a case in point. The Filet-O-Fish was invented by Cincinnati-based McDonald’s franchisee Lou Groen, who in 1962 needed a dining choice for his largely Catholic customer base. The Filet-O-Fish was a hit and is now on menus all year.

Today, many quick-service outfits, including Wendy’s, Jack in the Box, and KFC, offer fish sandwiches as a special during Lent. And experts say other operators would be wise to get on board with the season.

Laura McGuire of Chicago-based food industry consultancy Technomic says it’s imperative for restaurants to acknowledge their customer’s dietary restrictions during Lent.

“Alienating those who observe Lent on your menu could result in slower sales during this period,” she says, “as well as ultimately create customer dissatisfaction in the long term.”

Arby’s, known mainly for beef sandwiches, offers a fried fish sandwich on the menu from January through April. The company has been offering the sandwich for the last three years, but this is the first year it’s being pushed as a national promotion, says Arby’s spokeswoman Cathie Koch.

“Customers have come to expect a fish sandwich at Arby’s as a limited-time offer during the Lenten season,” Koch says. “It’s a popular addition to the menu.”

But others say Lent doesn’t have to just be about fried fish. Some quick serves, like Five Guys and Blimpie, use the opportunity to spotlight less-popular, year-round nonmeat menu items. Five Guys, for example, pushes its grilled cheese sandwich during the Lenten season.

As it’s done for the past three years, Blimpie is running a campaign during Lent this year to promote its tuna products. Its six- and 12-inch tuna sandwiches and tuna wraps are offered all year but are the stars of in-store point-of-purchase materials during Lent.

Last year, the in-store POP also focused on a tuna melt and tuna salad, but the company found that customers still chose subs.

“In previous years we’ve done additional products, but this year we’re really focusing on the subs and the wraps,” says Steven Evans, vice president of marketing at Blimpie.

“We want to make sure that our regular customers know that if they have any dietary restrictions on Fridays during the season, that we do have options for them.”

Some outlets use Lent as an opportunity to test new dishes that they may keep on the menu, depending on customer response.

“New fish- or vegetable-based offerings will not only appeal to those who observe Lent, but also attract seafood lovers and vegetarians,” McGuire says, adding that these offerings can draw new customers to the brand.

David Kincheloe, president of National Restaurant Consultants in Golden, Colorado, says one of his clients started offering lobster bisque on Fridays during Lent and sold out almost immediately. Now the restaurant is looking at adding the item to the year-round menu.

“[Lent] gives you a chance to experiment with a special that can grow into a full-time signature item,” Kincheloe says.

Skyline Chili, a brand with restaurants in Ohio, Kentucky, Indiana, and Florida, is serving up a twist on standard menu options during Lent. It added the Greek Pasta Bowl dish, a combination of Greek Salad and Skyline 3-Way Chili, but without meat or lettuce and finished off with a house Greek dressing.

Sarah Lapham, Skyline’s director of marketing, says the dish was conceived at the request of restaurant franchisees and employees, who already tried combining what was on the menu and tweaking it for Lent. The chain has a large Catholic customer base in Cincinnati in particular, she says, and pasta and Greek salad are both popular menu items.

“This is the best time for us to see the consumer reaction and how well it sits on the overall plan,” Lapham says.

But Skyline intends on keeping it a seasonal dish, maintaining focus on its core menu items and not diluting the brand. “We have a limited menu,” Lapham says. “We can perform better if we stay focused.”

And if a new menu item isn’t a hit with diners, Kincheloe says, another good thing about Lent is that it’s a limited time. “You have an excuse to take it off the menu,” he says.