Using a large sharp knife - cut pumpkin in half beginning from the top down one side of the pumpkin.
Scoop out the innards, saving the pumpkin seeds for roasting or planting later. Set pumpkin halves cut-side down on a large sheet tray (with sides) - use parchment paper for easier cleanup.
Roast for about an hour, checking every twenty minutes. (Cooking time will vary depending on the size of the pumpkin and efficiency of your oven.)
When the pumpkin has darkened and deflated a little, check to see if a fork easily goes through the pumpkin.
Remove from oven and let cool for at least an hour.
Peel the skin off of the pumpkin halves and discard.
Transfer pumpkin to food processor and purée until smooth - stir between pulsing.
Transfer purée to a cheesecloth set in a bowl and let drain for two hours - excess water will depend on how long the pumpkin has been cured.
Use immediately, refrigerate for a week or freeze for up to six months.
