It’s often said that breakfast is the most important meal of the day. So for Subway restaurant franchiser Hardy Grewal, it seemed natural to add an early morning menu.

Grewal, chief executive of L.A.-based OhCal Foods Inc., serves as the development agent for more than 1,000 Subway restaurants in Southern California and Ontario, Canada. (Subway is the biggest restaurant group in Los Angeles County.) Grewal helps the chain come up with and test products in the L.A. market before being considered for Subway’s more than 34,000 locations in 98 countries.

“We develop a lot of new programs here,” said Grewal. “We were the first market to offer breakfast. The company looked at our numbers in Los Angeles and made breakfast a nationwide offering starting about a year ago.”

Franchisees have long been a source of new menu items for restaurants. McDonald’s famous Big Mac sandwich was invented by a franchisee as was its Filet of Fish sandwich.

Grewal first experimented with breakfast in 2008 at the same time that Seattle-based Starbucks Corp. decided to do away with its breakfast sandwiches. The coffee chain said the sandwiches were profitable, but the smell overpowered the coffee aroma in its stores and diminished the café experience for customers.

A strong lunch crowd is Subway’s main source of business. By offering breakfast, stores must open earlier, creating longer hours for employees and more work: switching products at midday.

The lure of a $5 sandwich generates more revenue for the stores during the midday three-hour period than any other time. But the big lunch lines can drive away customers.

“People walk out of existing stores if lines are too long,” Grewal said. “So we have franchise owners open new stores nearby if there are high traffic counts.”

Meanwhile, the local Subway restaurants continue to develop new products. Local stores offer a healthy bread option, called 9 Grain With Omega-3. The bread choice could be added to the national menu if it is successful here.

“We change the products as we are evolving. We are always trying to find better, healthier products,” said Grewal.