Here's a recipe from Parade Magazine that looks very good. I'm going to try it first, and probably fix it for Thanksgiving. I consulted my former chef son, who says you can substitute canned pumpkin (3 pounds or 32 ounces - Trader Joes has 15 ounce cans and I will use 2 cans), but be sure it is plain pumpkin and not pumpkin pie mix.

Pumpkin Whip

Fresh pumpkin should be baked when being prepared for a recipe; it is too watery for boiling. This whip makes a tasty, colorful alternative to mashed potatoes.

2 pumpkins (about 4 pounds each)
1/4 cup (packed)
light-brown sugar
4 tablespoons butter
1/2 teaspoon ground ginger
1/4 teaspoon mace
1/4 teaspoon nutmeg
Pinch of cayenne pepper
1/4 teaspoon salt
1/4 cup sour cream

1. Preheat the oven to 375°F.
2. Halve the pumpkins, remove the seeds and fibers, then cut into wedges. Place the wedges, skin-side down, in shallow roasting pans to fit. Cover tightly with foil and bake until tender, about 11⁄2 hours.
3. Let the pumpkin cool, then remove and discard the skin. Place the pulp (or canned pumpkin) in a bowl and toss with the brown sugar, butter, ginger, mace, nutmeg, cayenne pepper and salt. (Ginny note - or skip steps 1-2 and substitute canned pumpkin - you probably won't have to puree if you do that, but just mix with an electrix mixer, as you would mashed potatoes)
4. Purée in batches in a food processor until just smooth. Transfer to a bowl; fold in the sour cream. Adjust seasonings to taste. Cover and reheat at 350°F in an ovenproof serving dish for 15 to 20 minutes. Serve.

Serves 8. Per serving: 180 calories, 28g carbohydrate, 3g protein, 8g fat, 20mg cholesterol.