01 -  Preheat oven to 350°F. Grease and line an 8x8-inch baking pan with parchment. 
 02 -  In a large bowl, whisk together mashed sweet potato, granulated sugar, eggs, vegetable oil, and vanilla extract until smooth. 
 03 -  In a separate bowl, sift all-purpose flour, baking powder, baking soda, salt, ground cinnamon, and ground nutmeg. 
 04 -  Gently fold dry mixture into wet mixture until just combined. Do not overmix. 
 05 -  Pour batter into prepared pan and bake for 35–40 minutes, or until a toothpick inserted in the center comes out clean. Allow cake to cool completely. 
 06 -  Crumble cooled cake into a large bowl. Add softened cream cheese, powdered sugar, and vanilla extract. Mix until smooth and mixture holds together. 
 07 -  Scoop and roll mixture into 1-inch balls, yielding about 24 portions. Place on a parchment-lined baking sheet and freeze for 15 minutes. 
 08 -  Melt white chocolate or white candy melts per package instructions. Color with food gels if desired. 
 09 -  In a small bowl, combine granulated sugar and ground cinnamon. 
 10 -  Dip each cake ball into melted chocolate, allow excess to drip off, sprinkle immediately with cinnamon sugar, and add candy eyes to create monster faces. Apply sprinkles if desired. 
 11 -  Return coated cake balls to parchment and chill for 10 minutes before serving.