Preheat oven to 375 degrees.
Mix shortening, sugar,and eggs well.
Stir in bananas, buttermilk, and vanilla extract.
Blend flour and baking soda. Stir into other ingredients.
Blend in nuts.(Optional).
Chill 1 hour. The dough will still be slightly sticky even after chilling.
For jumbo cookies, drop rounded tablespoonfuls onto lightly greased baking sheet. For smaller cookies use a teaspoon.
Bake at 375 for about 7-10 minutes or until light golden brown.
Leave unfrosted or frost with favorite flavored frosting.