Cantonese-style mooncakes. [Photo provided to China Daily]

With Mid-Autumn Festival approaching, gourmets are rushing to purchase custard mooncakes.

The coveted Cantonese-style mooncakes, with their delicate thin skin and their melt-in the mouth lotus paste and salted egg yolk filling, are produced by Hong Kong's Maxim Group.

According to a Nielsen research report, the award-winning mooncakes have been the best-selling mooncakes in Hong Kong for 19 consecutive years, and the tasty pies have a growing popularity in the Chinese mainland market.

"Our mooncakes are 100 percent made in Hong Kong with good quality ingredients. It's the best seasonal snack to share with others during the Mid-Autumn Festival, especially with hot tea," says Raymond Tong, Maxim Group's chief operating officer.

"The sales of our mooncakes in the Chinese mainland account for about 50 percent of our total sales. And we're making efforts to attract more mainland customers," he says.

The mooncakes are available in mainland supermarkets and the e-retailing platforms Tmall and JD, with prices between about 200 to 400 yuan ($ 30 to 60) depending on how many are in a box.

The company is also cooperating with the popular photo editing app Meitu to promote its mooncakes among younger consumers. And they have also partnered with Marvel and Disney to have characters such as Spiderman on the packages.