Debi Warner says:
1. Carve and clean out the pumpkin like you would if you were carving it for a jack-o-lantern. The only difference here is that after you have the inside cleaned out you are going to cut the pumpkin into large wedges.2. Take a 13x9x2 baking pan and fill it with about a 1/2 inch of water. Place the pumpkin shell side up into the pan. If you have a larger pumpkin, you might need more than one pan (I usually end up having 2.)
3. Bake in the oven at 350 degrees Fahrenheit for 1-1/2 hours or until the shell is soft enough for you to make an indention in it.
4. Remove from oven and allow to cool completely. Remove and discard the outer shell once completely cooled.
5. From this point, I usually use my food processor to blend the pumpkin until it is smooth. I usually only have to add a very small amount of water to do so. Use your judgment in how much water should be added. Your pumpkin mixture should be firm, but still pourable.
6. I then separate the pumpkin into 2 to 3 cup serving sizes and freeze them in Glad/Ziploc type freezer bags. Be sure to mark them with the contents and the date of preparation. Frozen pumpkin can keep up to 6 months! :)
HTH -- Have a great Thanksgiving!! :)