Pumpkin Soup:
Start with a real pumpkin -- "pie" or "sugar" variety is best. About 2-&-a-half to 3 lbs. is the size usually sold. Wash off outside of pumpkin with warm soapy water and a veggie brush. Wipe dry, pierce in several places on shoulder around stem end. (Note: see dianavan's posts above; this is important safety tip, not just hot air.) Place on cookie sheet or shallow baking dish. Bake at 350-375deg. F for 1 to 1-&-a-half hours. Remove from oven and let cool 1 hr. or overnight.
Have on hand homemade chicken stock, milk (whole or reduced fat), 1 med. lrg. yellow or white onion per whole pumpkin used, real butter, drinkable white wine.
To make soup: cut or break open pumpkin, remove seeds and stringiness of the seed pocket (note that these seeds can be removed from the stringy stuff, dried, salted, and used as snack; time and labor intensive.) Melt butter in bottom of good-size stockpot, coarse-chop peeled onion, begin sauteeing in butter (gently, not going for color on onions, just limp softness). Scoop pumpkin flesh out of its skin (handling flesh and skin reason to have washed pumpkin), add to onion in stockpot. Continue cooking, stirring frequently, even constantly. Pumpkin softens and mushes up and starts blending with onion. Add chicken stock -- this is a variable; depends on how much and how dry the pumpkin; about a quart to 6 cups of stock per whole pumpkin. When mass is bubbling, add milk (or half&half or cream), about half as much as stock. Bring back to a boil, turn down to a simmer, cook for about 1-&-a-half hours, stirring OFTEN, avoid scorching. (Kitchen will heat up during this process. At any point, a glass of cold, white wine and a brief sitdown with feet elevated would be a Good Thing.)   Turn off burner and get out other med. lrg stockpot or "saucepan". Puree mass from stockpot: with a blender -- 3 cups of the pumpkinstuff + 1 cup of (milk, or cream, or white wine), blend to velvet, pour into other pot; in a food processor -- 2 cups of pumpkinstuff, 2thirds cup of (m., c., w.w.), process to smooth, pour into other pot; strainer/colander -- press through into mixing bowl in 2 or 3 cup batches, add (m., c., w.w.) in similar proportions as above, stirring thoroughly. Use less wine than milk or cream. When you have several of these batches in the other pot, turn on burner under this pot and start cooking again, VE-E-ER-R-RY SLO-O-OW-W-WLY-Y, continuing to add more batches until original mass totally pureed, stirring FREQUENTLY. You are trying to force nutritional elements from the liquid into the pumpkin starch, I think, and "condense" the soup/expand the starch. You want to evaporate moisture, but watch closely and don't scorch. This should be an uncovered pot. after 1 or 2 hours remove from heat. Pack in covered containers/widemouth jars to give away, take to a potluck dinner, keep in the refrigerator.
To serve cold, plop several big spoonfulls into bowl, add dollop of yogurt or sour cream, sprinkle with chives or chopped parsley. To serve hot: place some thick pumpkin soup in a 1 or 2 qt saucepan, (add milk, cream, or stock if thinning desired), heat to boiling (stirring frequently), turn quite low and heat for 2 or 3 minutes. Serve in bowls with savory bread, something with real texture and chewiness. Sour cream swirled into the center of the bowl of soup is a tasty addition. Doesn't freeze well -- texture suffers, but flavor still good. Note above posts: baked, fresh pumpkin freezes well by itself.    Tw
P.S. Yes, time-consuming, labor-intensive -- kinda like "hard work". Also delicious, satisfying, warming, sustaining.