This cookie is a Christmas tradition started by my grandmother. She used to always mail them along with her "Minnesota Bars" (#162331).
I have a note on the recipe card that it was originally a winner in Pillsbury's 1st Grand National by Miss Laura Rott of Naperville, Illinois. (One bite and you'll know why it won.)
The original recipe called for one package of Rockwood Chocolate Mint Wafers. I've never been able to find them in the store so I use Andes Mint Baking Pieces. I'm sure you could also melt regular chocolate chips and add a little mint flavoring as well.
I posted the "refrigerator cookie" method because I think it's easier. You can also chill dough for just two hours, then enclose chocolate in 1 tbsp. of dough. Bake according to directions.
COOKING TIME INCLUDES FOUR HOURS OF CHILLING.