Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper. This makes it much easier to lift the pumpkin after cooking, as the sugars can cause sticking.
Carefully halve the pumpkin lengthwise and place it, cut-side down, onto the baking sheet.
1 pie pumpkin
Roast the pumpkin for about 40 minutes, or until the skin can be easily pierced with a fork in the thickest part of the pumpkin.
Let it cool on the baking sheet for at least 10 minutes before carefully turning the halves over (this will make them cool faster).
Once the pumpkin is completely cool, scoop out the flesh with a spoon and transfer it to a blender. Blend until very smooth.
Pumpkin puree can be stored in the fridge for about a week and freezes well.