Eating walnuts is the most brain-boosting. Walnuts are ripe in mid-September every year, and depending on the variety, there are many price brackets. Paper walnut because of the thin shell, full flesh, sweet flavor, and planting is not very large, the supply is not enough, so the price is relatively expensive, generally good varieties of walnuts in the non-origin area is more difficult to buy.

You can search on Taobao "Yuanmou people fruit workshop", his family in Kunming, specializing in Yunnan Dayao paper walnut, not bad. Below is a picture of a walnut from his home.