Good way to use up leftover baked/mashed sweet potatoes. I love them with a bit of honey. You could make a more savory version by omitting the sugar and cinnamon and adding a couple of T of minced onion.
In a medium bowl, stir together flour, baking soda, salt, sugar, cinnamon and milk powder: set aside.
In a large bowl, beat eggs. Stir in sourdough starter abd sweetpotato. Stir in flour mixture until just moistened; set aside.
Pour oil 3 inches deep in a medium skillet. Heat to 375 degrees. At this temperature, a 1 inch cube of bread will turn golden brown in 40 seconds.
Carefully drop batter by small Tablespoons full into hot oil. Fry 2 to 3 minutes on each side or til golden brown, turning once. Drain on paper towels. Sprinkle with cinnamon sugar. Serve hot with honey and butter if desired.