Ah.  I have seen Sweet Potatoes sprouted, but it never occurred to me that the leaves and vines, might be edible!

In fact, the tubers I saw,  were sprouted just for fun; in order to create luxuriant green vines.

Edible greens eh?  Good idea!

https://www.diynetwork.com/how-to/outdoors/gardening/how-to-plant-and-grow-sweet-potatoes

Folks seem to be recommending the same technique used to sprout an avocado seed.

Though I have seen Sweet Potatoes sprouted, just by placing a cut end piece on a plate, containing a 1/2 inch layer of water.

I experimented with both methods of growing slips, which is 1)suspending the sweet potato half in water just like you would an avocado or 2)  Laying the sweet potato on its side half submerged in potting soil. The potting soil method is the clear winner. I got roots but never did get slips from the water method. But have gotten probably 30 or 40 slips in the last 3 months from one single Japanese  sweet potato in a small plastic tub. Ive given some away, and still have more to share. I’m currently growing some of the slips in black pots in a warm place on my deck and haven’t decided whether to try a few in the garden under black plastic as well. I don’t know how successful I’ll be and producing potatoes  but a few of the gardeners in my garden group have successfully grown them under black plastic in gardens here in southern Washington outside Vancouver. If you are near Washougal id be glad to share some slips for you to try.