There are 2 shops near the A3 exit of Wanchai MTR station that I'll go to get my baking supplies. Both of them are located in the same building -- Simsons Commercial Building. The building faces the main road with the tram line but it's entrance is small. so have to really look out for it. The shops are
> Twins Baking Supplies on the 1F and
> Sweet Decoration Baking Supplies on the 13F
Many of their supplies like butter and cheese, flour and cake mix are cheaper than the supermarket. I like to buy the mooncake DIY kit come mid autumn festival. I did it with Ashley last year and we had a good time.
You can choose one of the 4 different flavours
1. red bean fillings with choclate snow skin
2. green bean fillings with chocolate snow skin
3. black seasame fillings with mango snow skin
4. red bean filling with green tea snow skin
One set cost HKD 94 and even comes with a nice paper box for you to put the completed moon cake. All you need to get besides this is the moon cake mould.
The mould comes in different shapes and sizes.