Cover cookie sheet with wax paper. Using ice cream scoop, drop cookies onto wax paper. Bake at 325 degrees for 15 to 18 minutes. Mix in egg and vanilla. Add flour and cornstarch and mix just until blended.
Drop cookes onto ungreased baking sheets.
Bake about 10 minutes or until light brown and firm to the touch. Add flour and salt. Bake crust at 350 degrees for about 20 minutes. Bake 20 - 25 minutes. Cool in pan.