ST. PETERSBURG — Ten years ago, Robert Earl opened the first Earl of Sandwich shop at Downtown Disney, serving its signature roast beef, cheddar and horseradish sandwiches to tourists seeking fast, affordable food.Since then, the chain has grown to 28 locations, including one in London, where another Earl — the 4th Earl of Sandwich — was credited with inventing the sandwich in the 1700s.Today, the Orlando-based Earl is champing at the bit to expand on a large scale, starting with the newest Earl of Sandwich in St. Petersburg. Sandwich sales reached $29 billion last year, up 4 percent from the previous year, according to Technomic's 2014 Top 150 Fast-Casual Chain Restaurant Report. The market for fast-casual restaurants, the middle ground between fast food and casual, sit-down places, continues to outperform the restaurant industry as a whole.The Earl of Sandwich in St. Petersburg, which opened last week at 5004 Fourth St. N, is the company's prototype for future franchises. The bright, modern design can be duplicated in virtually any city nationwide."We've been inundated with requests to develop a franchise model," Earl said. "We needed to come up with a model that was low cost to build, run and invest in."At 1,800 square feet, the restaurant is smaller than other fast-casual competitors, such as Panera Bread and Chipotle, but large enough for about 100 seats inside and on the patio. It can work in a shopping center end cap, a coveted restaurant spot, or sandwiched, so to speak, between other retailers. The typical startup cost is $300,000."This gives us the platform to be almost anywhere," said president and CEO Steve Heeley, who was hired in 2012 to revamp the menu and expand the chain. Previously, he served as chief operating officer of Au Bon Pain, a fast-casual bakery chain with about 300 locations worldwide.Earl of Sandwich seeks to add 50 to 60 restaurants by the end of 2015, an aggressive plan for a chain that did about $20 million in revenue last year. The company recently signed deals to develop stores in Phoenix and Qatar, and has plans for more restaurants in casinos, airports and interstate rest areas, places with high traffic.The chain has five locations at major airports and several at gambling venues, including the Planet Hollywood Resort and Casino. It also has three at service plazas along Florida's Turnpike. Its location at Downtown Disney, the highest-grossing store in the chain, draws 1.2 million people a year.Earl of Sandwich's founder is well-known in the restaurant business. Earl, 63, owns Planet Hollywood, a celebrity-themed restaurant founded with the backing of Hollywood stars Sylvester Stallone, Bruce Willis, Demi Moore and Arnold Schwarzenegger. In 2008, Planet Hollywood bought Buca di Beppo, a struggling Italian chain, which has grown to 100 locations and is now profitable, he said.Earl of Sandwich isn't the only fast-casual sandwich chain focused on expansion. Jimmy John's grew to more than 1,800 U.S. locations last year, an increase of 16 percent, according to the fast-casual report by Technomics, a research and consulting firm. Firehouse Subs expanded by 15 percent to 722 stores, and Jersey Mike's Subs expanded by 21 percent to 713 stores.The appeal is mainstream. Americans eat an estimated 300 million sandwiches every day — about one a day for every person, says US Foods, a top food distributor. And, if hamburgers are included, sandwiches account for nearly half of all sales at limited-service restaurants, where you order at a counter."The sandwich is an international item," Earl said. "The filling changes, but the basic concept, which the Earl of Sandwich created, has never changed."Earl Sandwich's concept revolves around the story of John Montagu, the 4th Earl of Sandwich. He was a British statesman and avid gambler who, not wanting to leave the card table for a meal, was known to ask for meat served between two slices bread.The restaurant chose API, a Tampa design and architectural firm, to create the prototype. Its charge was to design a space that would attract millennials and could easily be replicated."The management felt that the (older restaurant) interior was off-putting to the younger crowd," said Tom Henken, vice president and director of design for API. "They were looking to dial up the vibe a bit. With a name like Earl of Sandwich, it comes with some air of stuffiness."The result was a fresh, modern building with light wood floors and reddish-orange accents and fixtures. Text and graphics on the walls and ceiling tell the story of Earl of Sandwich and give a contemporary look to the logo, which shows the face of the sandwich inventor.To maximize sales, the chain introduced a dinner menu last year at most locations, with pastas, stuffed baked potatoes and pizza breads. Locations in Boston, New York, Tampa's International Plaza and now St. Petersburg offer delivery, a service that has proved successful for other chains, such as Jimmy John's.Earl of Sandwich is actively looking for sites in Clearwater and Sarasota and, like other chains, considers the fast-casual market far from saturated."I think the combination of price, quality and speed puts me right there in the top group," Earl said. "Everywhere in the world, people want a sandwich."Susan Thurston can be reached at [email protected] or (813) 225-3110.