In the bowl of an electric mixer, cream together butter and sugar until light and fluffy
Add egg and vanilla extract. Mix until combined.
In a separate bowl, combine flour, baking powder and salt. Add in increments to wet ingredients and mix until combined.
Chill dough in refrigerator for at least 1 hour.
Preheat oven to 350 degrees F. Roll dough into 24 1-2" balls and flatten with the bottom of a glass. Use flour if dough is very sticky.
Bake for 9-11 minutes (do not over-bake). Remove from oven and gently press a small indention into the center of each cookie with the bottom of a wooden spoon.
Allow cookies to completely cool. Break each mini pretzel in half to make antlers. You'll only need 48 halfs (24 whole mini pretzels), but account for some breaking and have extra.
Melt 1/4 cup chocolate chips until smooth.
Place a chocolate truffle into the center of each cookie. You can use melted chocolate to help it stay secure.
Use a toothpick and secure the candy eyes, red candy nose, and pretzel antlers onto the chocolate truffle using the melted chocolate.
Allow melted chocolate to set-up (2-3 minutes). Enjoy!