Piloncillo is Mexican dark sugar that is unrefined and has a high molasses content. You can find it at specialty supermarkets that carry Mexican products. Brown sugar can be substituted for the piloncillo.
Try serving this dish with its own syrup and drizzled with a little sweetened condensed milk.
This recipe can also be made with pumpkins or squash instead of the sweet potatoes.
You can eat this dish warm or you can let it cool, refrigerate it and eat it cold. It will keep in the refrigerator, covered, for a week.