McDonald's Corp. is moving to toast its sandwich buns longer and change how it sears and grills hamburgers as part of its effort to reinvigorate growth with "hot, tasty food."

The increased toasting time makes the sandwiches hotter, while the new grilling technique produces juicier burgers, Steve Easterbrook, the restaurant chain's global chief executive officer, said at an investment conference in New York on Wednesday.

"These little things add up to big differences for our customers," Easterbrook said. "We're recommitting to tastier food across the menu."

Easterbrook, who took the CEO job in March, is trying to pull the company out of a prolonged slump. Global sales fell in 2014 for the first time in more than a decade as nimbler rivals picked off customers with menus that appeal to a growing consumer appetite for fresher, less-processed food. In the US, the burger chain has posted declines for six straight quarters. Earlier this month, Easterbrook laid out a turnaround strategy that included cost cuts, a leadership reorganisation and a plan to sell about 3500 company-owned restaurants across the globe to franchisees.

But that plan didn't focus on the details of the food, something Easterbrook sought to address on Wednesday. He also said McDonald's would stop providing monthly sales figures, an effort to nudge investors away from short-term results.

Easterbrook sees turning around the US business as a "burning priority," saying that an emphasis on convenience and value will bring customers back to McDonald's in its home market. As part of the push, it's testing a slimmed-down menu for drive-thru customers, offering about half as many items as usual. Drive-thru orders account for about 70 per cent of US sales, so improving that experience is crucial for McDonald's.

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