Step 1

Prepare and bake cake according to package directions, using a greased 13-in. x 9-in. baking pan. Cool on a wire rack for 1 hour.

Step 2

In a small bowl, dissolve gelatin in boiling water; stir in cold water.

Step 3

With a meat fork or wooden skewer, poke holes in cake about 2 in. apart.

Step 4

Slowly pour gelatin over cake. Refrigerate for 2-3 hours.

Step 5

For frosting, in a small bowl, cream butter until fluffy. Beat in the confectioners' sugar, cocoa, milk and vanilla until smooth.

Step 6

Spread over cake; top with candy pumpkins, candy corns and sprinkles. Cover and refrigerate until serving.