Best Shortbread

It's not like Walker's but it's excellent. I am sure you could just add mini choc chips to the recipe to make the choc ones.

1 lb. butter at room temp.
1 cup sifted confectioners/icing sugar
1/2 cup cornstarch
1 tsp. vanilla
3 cups all purpose flour

Cream butter and icing sugar until very fluffy. Beat in cornstarch, vanilla and then flour. Beat until very light. Drop teaspoonfuls on to a lightly greased baking sheet. Bake at 325 degrees F for 20 to 25 min or until a light golden brown. Don't overbake.