Cover a baking sheet with waxed paper. In a large saucepan melt the 3 tablespoons margarine or butter. Add the marshmallows. Cook until the marshmallows are melted, stirring constantly with a wooden spoon. Remove from heat.
Add popped popcorn and puffed corn cereal to the pan. Quickly stir the mixture with the wooden spoon until the popcorn and cereal are coated with the marshmallow mixture. Stir in the candy corn. If mixture is too hot to touch, wait a few minutes until it cools slightly.
Rub some softened margarine or butter over your hands. Use your hands to shape the mixture into eight 4-inch-long logs that look like ears of corn. Push a wooden stick into the end of each ear. Place on prepared baking sheet. Let cool completely. Serve the same day. Makes 8 corn cobs.