I used to think snickerdoodles were sugar cookies with cinnamon on top, but not Nigella's version. Just like her description these little gems are like "oven-baked doughnuts - small, cinnamony, with a drier crumb than the dunkin' sort". However, I have yet to decide whether I like them that way.
Preheat oven to 350F.
In a large bowl cream butter with 1/3 cup sugar. Beat in the egg and vanilla until smooth. Add dry ingredients (flour, nutmeg, baking powder, and salt) and mix to form dough.
Mix cinnamon and 2 tbsp sugar together in a shallow bowl. Make balls out of the dough and then roll them in the cinnamon-sugar. Arrange on a nonstick baking sheet. Bake for 15 minutes. Cool on wire racks. Enjoy!