All recipes are for 2 servings unless noted. Oil is canola oil and salt is kosher salt.


Yakiimo / roasted Japanese sweet potato

A much-beloved snack in fall and early winter. When I was a child, a vendor pushing a cart filled with blackened rocks and reddish-purple sweet potatoes would come around the neighborhood, chanting, "Roasted sweet potatoes! Rock-roasted sweet potatoes!" in a slow, time-honored cadence. If you started to get ready (asking parents to pitch in some cash) when you first heard the chant, the vendor would be near your house by the time you dashed out the front door. The man at the cart would dig through the rocks and find some big, beautiful sweet potatoes, wrap them in newspaper and hand them to his young customer. The warmth and the mellow smell were so rewarding, and needless to say the sweet taste was a big hit after running back to the house. Later the cart became a small truck and the chant was replaced with a recorded voice on a loudspeaker, but the melody was still the same. I wonder if those vendors are still coming around the neighborhood. Yakiimo is also a favorite when family or friends gather to clean up the yard and burn fallen leaves, providing a perfect place to roast these fall treats.


Satsumaimo Japanese sweet potatoes

Start heating the oven to 150-160 C (approx. 300-320 F).


Wash satsumaimo, and wrap in foil without drying surface.

Put in the oven (oven does not need to be fully preheated to set temperature), and roast for 1-2 hours.
Roasting for 70-80 minutes is usually enough.
If unsure, check by inserting a skewer.

If time allows, leave satsumaimo in oven for another 30 minutes or so after turning it off.


Serve hot.

  • Yakiimo is normally eaten as is. Forget about butter, Tom, and enjoy what it offers.
  • Roasting at a relatively low temperature results in the distinctive sweetness.
  • If you use rocks to mimic traditional rock-roasted sweet potatoes, enough rocks to cover sweet potatoes should be used, ideally. Some people say a 3-cm-layer of rocks at the bottom is good enough. In either case, preheat rocks in a thick-walled pot and place satsumaimo as is or wrapped with foil, and roast in the pot, covered, in oven or stovetop. 
  • When making yakiimo in a burning pile of yard debris, wrap satsumaimo in foil as above, and place them in a smoldering area of the fire. Too much heat would simply char them. 
  • Leftover yakiimo makes a great ingredient for sweets.

Recipes with yakiimo

(Last updated: September 7, 2017)


Anonymous said...

Hi Neco,

We love Japanese sweet potatoes in our household. We used to steam them but the texture is very touch and go or should i say hit and miss! We only discovered how delicious they were when roasted when we went to Genting Highlands, Malaysia for a holiday.

Thanks for putting up the instructions here. I had forgotten how it was done.


neco said...

Very welcome. Enjoy the sweet potatoes!