Combine all ingredients (except powdered sugar and Hershey's Kisses) in a large mixing bowl and blend well.
Chill 1 hour or more.
Roll chilled dough into 1 inch balls and roll in powdered sugar.
Bake on parchment-lined baking sheet at 300 degrees for 18-20 minutes.
Remove from oven and immediately place Hershey's Kiss in the center of each, pressing down slightly.
Cool completely on a wire rack.