Prep pan and hands: Line a baking sheet with parchment paper and spray your hands lightly with nonstick cooking spray before you start shaping.
Melt the butter: In a large pot over low heat, melt the butter completely, about 1 minute, stirring so it doesn't brown.
Melt the marshmallows: Add the marshmallows to the pot and stir constantly until the mixture is smooth and no lumps remain, 3 to 4 minutes.
Stir in cereal: Remove the pot from heat and fold in the Rice Krispies cereal until every piece is evenly coated and sticky.
Let it cool slightly: Let the mixture rest for 3 to 5 minutes until it's cool enough to handle but still warm and pliable.
Roll into balls: Grease your hands again and scoop about 2 tablespoons of mixture per piece, rolling into roughly 20 balls.
Shape pumpkin ridges: Press each ball gently from top to bottom and pinch vertical lines with your fingers to mimic pumpkin ridges, then flatten the bottom so it sits flat.
Make a stem indent: Use the back of a spoon or your finger to press a small dent into the top center of each ball for the stem.
Melt the candy coating: In a microwave-safe bowl, melt the orange candy melts with the shortening in 30-second bursts, stirring between each, until smooth.
Dip each pumpkin: Dip or roll each shaped ball in the melted orange coating, letting the excess drip off, then set it on the parchment-lined sheet.
Add stems and faces: Press a licorice piece into the indent for a stem and add mini chocolate chips for a simple jack-o-lantern face if desired.
Let the coating set: Let the pumpkins sit at room temperature for about 15 minutes until the coating firms up completely before serving or packing.
