In a medium sized pot, add the stock and bring to a boil. Add the sweet potatoes, and boil.

Heat the olive oil on medium heat in a large skillet; add the onion and cook until they are translucent and soft (but not browned). Add the rice and stir with a wooden spoon about 3 minutes. Add the Prosecco (or white wine) and cook about 1-2 minutes stirring with the wooden spoon.

Add a 4 to 6-ounce ladle of broth and cook, stirring, until it is absorbed. Continue adding the broth a ladle at a time, waiting until the liquid is absorbed before adding more. Remove the sweet potatoes from remaining broth and mash them quickly with a potato masher (mash them enough so that they’re in very small pieces). Add the potatoes and remaining broth. Cook until the rice is tender and creamy and yet still a little al dente, about 15-20 minutes. Remove the pan from the heat. If making this vegan, use margarine and omit the cheese. Stir in the butter and cheese until well mixed.

Ladle the risotto on individual plates and decorate with figs and a drizzle of the aged balsamic vinegar; serve immediately.