"The shallot version is for diners who don't eat spicy food, while the homemade style features a special kind of Sichuan pickle that includes cowpea, ginger and chili," Xie says.

The pepper sauce is Xu's own creation, which is made using a mix of fresh green peppers, green chili and a special sauce. After a fish is steamed and the sauce is poured over, a carpet of chopped green chilis is added.

"The fresh green peppers have a sweeter aftertaste compared to dried peppers, yet the numb flavor is less strong than the dried ones," Xie says.

"The flavor of the pepper sauce does not belong to the 24 traditional flavors of Sichuan cuisine, and wild fish was not a common sight on dinner tables, until recently. The new flavor Xu created for the wild fish has made the dish popular now," the chef explains.