Bake your chocolate cupcakes ahead of time, let them cool completely, and set out your frosting, food coloring, and decorations so everything is ready to go.
For the spider cupcakes, spread white frosting on each cupcake, pipe four chocolate legs on each side with a #5 tip, press a cookie in the center, then add two small dots of frosting on top of the cookie and place candy eyes.
For the witch cupcakes, tint about 2 cups of frosting green, pipe a flat swirl with a 1M tip, place a cookie in the center, add a small dollop of purple frosting, and finish with a chocolate drop on top to look like a witch’s hat.
For the pumpkin cupcakes, tint about 2 cups of frosting orange, pipe stripes using a #47 tip with the flat side up, use chocolate frosting with a #5 tip to draw the face, and add green frosting for the stem.
For the monster cupcakes, divide frosting into purple and green, pipe swirls with a 1M tip, and press candy eyes randomly over the top.
For the Mickey cupcakes, split frosting into three parts and tint one yellow, one orange, and leave one plain, pipe a flat swirl of yellow frosting and chill 10 minutes, repeat with orange, chill again, then finish with white frosting on top, and press two chocolate discs or mini cookies into the sides for ears.
Store the decorated cupcakes in the refrigerator for up to 3 days, keeping them covered so the frosting stays fresh.