Mix in a bowl the flour, cornstarch and baking powder.
In a separate bowl, cream the butter, sugar, egg and vanilla extract.
Stir flour mixture into the remaining creamed ingredients gradually, until blended.
Cover and chill for 15 minutes or longer.
Roll dough on floured surface to 1/8 inch thickness and cut with Christmas-shape cookie cutters. Place on greased cookie sheets and decorate with sprinkles (or icing could be used, after baking). Pierce a small hole through each cookie, toward the
top center portion (use a barbecue skewer).
Bake at 350 degrees F for 8 minutes. Cookies are still pale-colored when finished, not browned.
Cool on a cookie sheet.
Store in an airtight tin for 2 to 3 weeks.
Use yarn or wire ornament hangers to hang cookies on your Christmas tree.