Preheat oven to 425 degrees. Cream the butter, egg, vanilla, and sour cream together.
In a separate bowl, whisk together 3 1/4 cups flour, sugar, baking soda, salt and nutmeg. Mix into wet ingredients. Dough will be sticky.
Dust board with just enough reserved flour to easily work the dough. Roll out to about 1/4-inch thickness. Cut shapes and place on ungreased cookie sheet. Sprinkle with sugar or colored sugar for a touch of sweetness.
Bake at 425 degrees, hot oven for about 8 minutes until bottoms start to brown. Cool on sheet a few minutes before moving to rack to cool completely.