Sweet potatoes are a staple starch in many cuisines across Asia and are more commonly known as yams in the Americas. They were and are still a cheap and nutritious source of carbohydrates that is also packed with vitamins and minerals, which explains its origins as a staple food during past war periods. They also tend to range from a more traditional style of roasted sweet potato or sweet potato porridge to a more modern take with fries.
In Tokyo, the tradition of charcoal roasted sweet potatoes (yaki-imo 焼き芋) is fortunately still very much alive. The magic appears at night in the form of the yaki-imo man! Basically a food truck that has a charcoal burner in it, the yaki-imo man usually makes his rounds around residential estates. I personally have not seen many going around, but it is hard not to spot if one is nearby. A strange song blasts from the mini van while it slowly drifts down the street. The sound of “Yaaaakiii iiiimoooo… Yaaaakiii iiiimoooo…” fills the air. In the dark of the night, the red lanterns hanging from the truck that have the words “yaki-imo” on them have an eerie look to them.
The yaki-imo men are grandfather-like figures, and tend to be very kind and friendly. There may be more than one type of sweet potato on offer, such as satsuma-imo (さつまいも) which has a yellow body, or beni-imo (紅芋) or murasaki-imo (紫芋) which are purple. The sweet potatoes are roasted over charcoal, which imparts a smoky oaky aroma to the skin. The skin is edible but some prefer to have it peeled. The potatoes are sold whole and by weight, for about 500 yen for a 300g piece.
These traditional yaki-imo men do not frequent the bustling city areas of Tokyo, so if you don’t happen to see any yaki-imo trucks on the streets fret not. Warm and fragrant roasted sweet potatoes are still available at supermarkets but if you do find yourself in the right place, at the right time, keep an eye and ear out for the yaki-imo men.