In a mixer bowl, cream together sugar and butter; beat in egg and vanilla.

Combine flour, cinnamon, baking powder and salt.

Add to butter mixture.

Blend well.

Cover and refrigerate 2 hours or till firm enough to roll into balls.

Shape dough into small balls about 3/4-inch in diameter.

Roll in cinnamon sugar to coat.

Set cookies 1-inch apart on lightly greased cookie sheets.

Bake at 350° for 10 minutes or till the edges are lightly browned.

Cool slightly on pans, then remove to racks to cool completely.