Sterilize the 3 jars in boiling water, drain, and allow to dry completely.
For the pumpkin: Peel the shiny, hard orange rind off the pumpkin and discard it. Cut the pumpkin into 2in/5cm rings. Use a spoon to remove the seeds and fibers while keeping the flesh. Place the flesh on a flat surface and stamp out shapes using your favorite cookie cutters or cu