Preheat oven to 400°F. Line a large baking sheet with parchment paper.
Use a sharp knife to remove stem from pumpkin. Slice a thin piece from one side of pumpkin to level and prevent it from rolling.
Cut the pumpkin into 2 equal halves.
Use a large spoon to remove the stringy pulp and seeds from each half.
Lightly season with salt then place cut side down on baking sheet.
Bake for 35-40 minutes or until a paring knife easily slides through the flesh, Test several different areas of the pumpkin. (A smaller pumpkin may need slightly less time)
Cool on the pan on a cooling rack for 1 hour. The skin will begin pulling away from the pumpkin as it cools.
Remove pumpkin from skin. Puree in batches in a food processor until smooth. Cool completely.
Store chilled in an airtight container for up to one week or frozen for up to 3 months.
Stir well before using.