How do get the "caramelized juices" from yams

This is hard to ask, but you know how when you bake a yam for long enough it will ooze the caramelized sugars? It's like... it's leaking sap.

BUT The most delicious sap ever. So wondering, is there a way to cook the yam so that it entirely becomes the caramelized sugars, and then how would you store this?

Seriously so amazingly good.