• 1 onion, peeled and finely chopped
• 2 to 3 tablespoons butter
• 2 cups strong turkey or chicken broth or stock
• 1 pound winter squash, peeled and cut in manageable chunks (banana squash, Hubbard squash, butternut squash, acorn squash or pumpkin)
• 2 to 3 ounces pistachios, shelled
• 3/4 cup heavy cream or whole milk
• salt, white pepper, nutmeg, cinnamon to taste
1. Use a heavy-bottomed 3- to 4-quart saucepan to sauté the onion in half the butter until soft. Add the stock and squash. Cover the pan and let cook, covered, for at least 1 hour, preferably 2. Stir the mixture occasionally to prevent sticking and scorching.
2. Puree the soup in a blender or food processor. If there are strings or fibers, strain it through a sieve. Return the soup to a clean pan.
3. Chop the pistachios and toast them in a baking pan in the oven just for a couple of minutes, to bring up their aroma. Set them aside.
4. To finish the soup, bring it to a boil and add the cream. Season it to taste. Add in the remaining butter and immediately remove the soup from the heat. Do not let it boil. Whisk the butter in until it melts. Serve it garnished with the chopped pistachios. Serves 6 to 8.