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 and 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 degrees for 10 minutes or till the edges are lightly browned. Cool slightly on pans, then remove to racks to cool completely.
Ready in 30 min