In a large bowl, cream vegetable shortening, butter, sugar, and brown sugar until light and fluffy; stir in eggs and vanilla extract. Add flour, salt, and baking soda; stir until well blended.
In a small bowl, combine dates and nuts until dates are coated with nuts; stir into cookie dough.
Shape cookie dough into a 2-inch wide logs, wrap in wax paper or plastic wrap, and refrigerate at least overnight. When it is rolled up, twist the ends tightly. Dough may be stored in the refrigerator for several days before using.
Preheat oven to 350 degrees F. Lightly grease cookie sheets.
When ready to bake, remove dough from the refrigerator. Using a sharp knife, cut cookie dough into 1/8-inch slices; place 1-inch apart onto prepared cookie sheets. Slice only what is to be baked, return remainder to refrigerator for baking as needed. Dough will last approximately 1 week in the refrigerator. Any longer storage, store in the freezer.
Bake 10 minutes or until light brown. Remove from oven and cool on wire racks.
* Butter may be substituted for the vegetable shortening.
Old Fashion Refrigerator Cookies Recipe - Icebox Cookies: https://whatscookingamerica.net/cookie/refrigeratorcookies.htm