Kintoki sweet potato; red-skinned sweet potato
Refers to any of several sweet potato cultivars with reddish skin, often associated with a sweet, dense flesh. Commonly used in Japanese cooking and confectionery.
I love sweet potato desserts made with Kintoki sweet potatoes.
Farmers around here grow a lot of Kintoki sweet potatoes.
金時 (Kintoki) likely refers to the legendary strong boy Kintarō, suggesting a robust, reddish quality, combined with 芋 (imo, 'potato'). The exact origin of the cultivar name is uncertain.