This cake got its name as its round shape and brown color are quite like crab shell. It is firstly prepared from oil and fermented flour into flat round biscuit, and then toasted in oven with some sesame stained on the surface. The cake tastes delicious, and moderately sweet and salty, and the surface is quite crisp. Once, someone wrote a poem for the cake “smell the taste of the cake even without seeing it, and the crisp surface falls only with a small bite”. Basically, there are two kinds of cakes, namely sweet and salty. For salty cakes, the filling is made from oil and shallot, fresh meat, crab meal, and shrimp, while for sweet one, the filling is from white sugar, rose, sweetened bean paste, date jam.This cake is best made by Wu Wan Cake House located near intersection of Shimenyilu and Weihaiwei Road.