For the spiced pumpkin purée, bring a small amount of water to a simmer in a pan. Suspend a steaming basket above the water (do not allow the base of the basket to touch the water). Add the chopped pumpkin and steam for 15-20 minutes, or until tender. Remove from the steaming basket and set aside to cool.
When the pumpkin has cooled, transfer it to the bowl of a food processor. Add the orange juice, allspice and honey and blend until smooth and well combined.
For the cocktail, mix together the pumpkin purée, pineapple juice, grenadine and crushed ice in a large jug until well combined.
Chill in the fridge for at least one hour.
To serve, pour the mixture into a large bowl (preferably skull-shaped). The mixture should half-fill the bowl. Top up with the lemonade. Mix well. Ladle into cups and garnish with Halloween jellies.