Beat egg whites with an electric mixer until soft peaks form. Gradually add sugar and beat until stiff peaks form. Fold in the pecans and chocolate chips. Drop by teaspoonfuls onto a prepared cookie sheet. Put cookies into the preheated oven and turn off the oven, keeping the door shut. Do not open the door until the next morning. Then the cookies should be done. It is best to do this at bedtime so the waiting is easier.