KFC says it would be happy if it sold half the number of Double Down burgers it did when the product was launched in New Zealand last year.
The burger - which consisted of bacon and cheese sandwiched between fried chicken fillets instead of bread - alarmed heath advocates, but proved a hit with customers.
KFC's owner, Restaurant Brands, now plans to return it to the menu temporarily, in a bid to boost sales, which slumped in the 12 weeks to the middle of May.
RBL chief executive Russel Creedy says sales have not been as strong when the burger was relaunched for a second time overseas.
''Promotions second-time around generally make 50% - 60% (of the first round),'' he said.
''We expect to be nowhere near the frenetic purchasing that went on the first time, (when) Suppliers really struggled (to meet demand).''
The company's shares fell 4 cents to $2.07 each.