Preheat oven to 350 degrees. Line or butter 16-18 muffin cups.
In a small bowl, combine 1/2 cup sugar and cinnamon; set aside.
In a large bowl, cream together butter and 1 cup sugar until light and fluffy, about 3 to 5 minutes. Pour in the vanilla. Beat in the eggs one at a time until fully combined
In a separate bowl, combine flour, baking soda, baking powder, cream of tartar and nutmeg.
Add the flour mixture, and the sour cream alternately to the butter mixture, beating after each addition. Start with the flour and end with the flour. Scrape the bowl occasionally.
Using an ice cream scoop, scoop out muffin batter one at a time and drop into the cinnamon sugar mixture. Roll the muffin batter around in the mixture until it is covered completely in cinnamon sugar. Place muffin into muffin tin. Bake for 18-20 minutes or until golden brown.