Melt the butter in a large non stick pan on low heat. Add the marshmallows and stir to combine. Once slightly melted begin adding orange food coloring until you reach the desired shade.
Keep stirring until marshmallows are completely melted. Turn off heat and add Rice Krispies, one cup at a time. Stir after each addition. Let cool slightly until you are able to handle the mixture.
Lay down a sheet of parchment paper and coat your hands with cooking spray. Take large portions of the Rice Krispie mixture and form into balls. Keep them uniform in size or make different sizes.
Press down on the top and bottom of each ball to form into a pumpkin shape. Use your finger to make a dent in the top for the pretzel rod. Set on parchment paper.
Place pretzel into the middle of the top of the pumpkin and press down slightly so it sticks.
Use scissors to cut little leaf shapes out of the Airheads.
To form the vine, cut along the long part of the Airhead very thinly, roll out into a small rope. Wrap it around something thin like a skewer stick to make a twisty vine.
Gently pull off the skewer and stick to one side of the pretzel and stick the leaf on the other side, repeat for all the pumpkins.