Break pretzels into pieces to use as antlers.
Preheat oven to 350.
Cream together peanut butter, butter, sugar and brown sugar until smooth.
Add egg and vanilla and beat until smooth.
Whisk together flour, baking soda and salt in a separate bowl.
Slowly add dry ingredients to the creamed mixture, beating until incorporated.
Roll into 1/2-3/4" balls and place on cookie sheet several inches apart.
Sprinkle with sugar and gently make an indentation slightly off the center of each cookie.
Bake 12-14 minutes.
Place an M&M in the indentation of each cookie.
Insert 2 mini chocolate chips (pointy side down) above the M&M to be the eyes.
Insert 2 pretzel pieces to be the antlers.
If the antlers won't stick, place some chocolate chips in a sandwich bag and microwave 30 seconds and knead until soft. Clip the very tip of the corner and pipe onto cookie to act as glue.