Preheat oven to 350 degrees F. Place 24 paper baking cups in muffin tins. Add 3/4 cup of mini chocolate candies to batter. Mix well. Spoon batter evenly into baking cups and bake according to package directions. Let cupcakes cool,then frost with vanilla frosting.
Decorate cupcakes by sprinkling top 1/3 and 1/2 down one side of each cupcake with red sugar crystals,making hats. Use green chocolate candies for eyes and red ones for noses. Cut 2 mini marshmallows in half length wise.
Place 3 pieces of marshmallow at edge of red sugar to make hat brims. Place remaining piece at end of red sugar on sides to make hat tassels. Make beards by placing marshmallows in two rows over bottom one-third of frosting on each cupcake. Serve,or cover loosely until ready to serve.