Many oolong teas can do well with a light firing right before you brew.
Spot firing/roasting is when one uses a heat source on the tea prior to brewing it. This can give an oolong a fuller flavor & aroma, and more body for the brew.
My first attempt at spot roasting was with my rice cooker and an aged Baozhong. The tea had picked up some extraneous smells from storage. I just stuck it straight into the cooker, put the lid down and put the stuff through two cycles of “cooking,” immediately brewing it afterwards. It tasted much better afterwards, free of the unpleasant musty/sour taste, but without loss to the soft, slight tartness & smoothness of aged tea.
Sometime late last year, I found myself trying to find different sources of aged oolongs in the US. Through one of my online searches, I came across Imen of Tea Habitat’s blog called “Tea Obsession.” In particular, the search brought up a link to her article on Chaozhou-style open-flame roasting, which can be found here:
It was brilliant, the first time I had found someone talking in length about what I had only previously heard of through rumors. Imen even included clear instructions and pictures on how to spot roast with nothing more than a flame and a piece of paper – awesome!
Afterwards, I dug up more information on roasting with other materials and types of flames. Aside from paper, I’ve seen specialized single-serving spot roast equipment made of metal or clay, and I’ve even used an old Yixing pot for roasting. I still prefer paper for a spot roast as it takes less time than a clay pot to heat up, although one must be careful not to burn a hole in the sheet. I find that moving the paper around over the flame and gently tossing the tea produces good results; 5 to 10 minutes of roasting should be sufficient.