2. Remove from the oven. When cool enough to handle, cut in half. Scoop out the seeds and fibers and discard. Scoop out the flesh and pass it through a food mill placed over a bowl, or mash it with a potato masher. It should yield approximately 3 cups of puree.
3. Warm the olive oil in a sauté pan over low heat. Add the onion and sauté until very soft, about 15 minutes. Add the pureed squash and season with salt and pepper. Add the lemon zest and cinnamon.
4. Cook over very low heat, stirring often, until dry, about 10 minutes. Transfer to a warm serving dish and sprinkle with mint, parsley or rosemary, if desired.