We recommend going with all chocolate in order to mimic the dark color of a spider. But you can get creative and use any color cake or frosting you'd like. You'll also need chocolate frosting, chocolate sprinkles, black string licorice, some cinnamon candies and mini-marshmallows.
Start out by baking your cupcakes as usual. Use Halloween-themed liners for fun. Once the cakes are completely cooled, frost generously. Then dip the tops into the chocolate sprinkles to make the spider's body look fuzzy. Using scissors, cut eight 4-inch legs from the licorice. Stick the legs into the cupcake, four on each side. You can bend them in half so they look more realistic.
Cut the marshmallows in half and stick them on the cupcake to make eyes. Using a bit of frosting as glue, affix a cinnamon candy to each marshmallow.