Like roasted chestnuts? Then you’ll love Chinatown. You can find dozens of these vendors around Chinatown, especially around the popular Yaowarat Road.
These roasted chestnuts are not just tasty, but they are also very healthy. A big bag costs around 100 baht, and is more than pretty much any chestnut lover could eat on his own. These are Chinese chestnuts, also known as Castanea mollissima.
From wikipedia: The nuts are edible, and the tree is widely cultivated in eastern Asia; over 300 cultivars have been selected for nut production, subdivided into five major regional groups: Northern, Yangtze River Valley, Sichuan and Guizhou, Southern and Southwestern. Besides that, the Dandong chestnut (belonging to the Japanese chestnut – Castanea crenata) is a major cultivar in Liaoning Province. Some cultivars, such as ‘Kuling’, ‘Meiling’, and ‘Nanking’, have large nuts up to 4 cm diameter. The nuts are sweet, and considered by some to have the best taste of any chestnut, though others state they are not as good as the American Chestnut. The nuts also provide a significant food source for wildlife.
Just make sure to drink something along with the chestnuts, as they otherwise tend to make your mouth feel a little dry.