How To make Mom's Cookie Press Shortbread

2 c Brown sugar, sifted
4 c Butter
8 c Flour
2 ts Salt (omit ?)
1 c Cornstarch
1 c Icing sugar
Directions: Mix well, put in cookie press and put cookies on ungreased cookie sheet. Bake at 325 approx 20 minutes. Cookies should not brown too much.