Combine the sweet potatoes, buttermilk, egg, butter, sugar, yeast and salt in the bowl of a stand mixer. Mix on low until combined. Let the mixture sit for a few minutes.

Using the paddle attachment, add in 1 cup of the flour. Add in more flour, 1/2 cup at a time, until a soft dough forms. If you are using a stand mixer, switch to the dough hook and knead the dough for 6-7 minutes, adding more flour as needed to form a dough that is tacky but not overly sticky.

Scrape the dough from the bowl and form into a smooth ball. Grease a large bowl and place the dough in the bowl.* Turn the dough to coat in oil. Cover with a towel or a piece of plastic wrap that has been sprayed with nonstick cooking spray. Let the dough rise until it has doubled.

When the dough has doubled, punch the dough down and turn it out onto a counter that has been lightly floured. Cut the dough into 3 equal pieces.

Working with one piece at a time, roll the dough into a circle about 12-inches in diameter. Use a pizza cutter to cut the circle into 12 wedges.

Starting at the wide end, roll up the wedges into a crescent shape. Place the rolls on a baking sheet lined with parchment paper or a silpat liner. Repeat with the remaining 2 balls of dough.

Cover the rolls loosely with a towel and let the rolls rise again until doubled.

While the rolls are rising, preheat the oven to 350ºF.

Once the rolls have doubled, bake them in the preheated oven until they are browned and cooked through, 15-20 minutes.

Melt the butter while the rolls bake.

Remove from the oven and brush with the melted butter.