Satsumaimo (sweet potatoes) are mashed and made with sugar into a sweetened puree (an), to which whole or crumbled candied chestnuts are added. Dried gardenia pods (kuchinashi no mi) can be added to enhance the yellow-golden color, although this is not an imperative as satsumaimo already have a yellow color of themselves.
The puree is eaten with a spoon. The taste is rather sweet, but not unpleasant.
This dish is part of osechi-ryori, the traditional New Years dishes, which always have an auspicious aspect. In this case it is the "gold" color (which also appears in the name, "kinton" could be pieces of gold), which suggests wealth and prosperity in business. Note that, despite its sweet character, this is not a dessert!