• Preheat oven to 350 degrees.
• Spray bundt pan with cooking spray.
• Combine sugar and cinnamon in a small bowl and sprinkle evenly to coat bundt pan. Shake off excess and save it for later. Set pan aside.
• In a large mixing bowl combine cake mix, pudding, nutmeg; stir to combine, then add egg nog, sour cream, eggs, oil, water and blend until well combined.
• Pour batter into prepared pan.
• Sprinkle leftover cinnamon/sugar mixture over the batter.
• Bake 35-40 minutes, until toothpick inserted in center comes out clean.
• Remove from oven and let cake rest on cake rack in the pan for 10 minutes.
• Turn out cake onto cooling rack and let cool completely.

To make the Frosting

• In a mixing bowl cream butter, vanilla, and eggnog. Add nutmeg, salt, and powdered sugar 1 cup at a time. Blend well until smooth and loose, adjust as needed with more egg nog or powdered sugar to get a good consistency.
• Put cake on serving platter, spoon frosting around the top of cake and let it drizzle down the sides. If desired, grate some fresh nutmeg to garnish top of cake