Preheat oven to 475°F. Line a large baking sheet with parchment paper.
Carefully slice the squash in half vertically, from stem to bottom. Scoop out and discard the seeds.
Peel only one of the halves and dice it into 1/2" cubes to equal about 2 1/2 - 3 cups (the exact amount will depend on the size of your squash). While you are cutting the cubes, also be sure to cut a triangle that you will save to be the turkey's beak. (You will not roast the triangular beak – set it aside until you assemble your turkey.)
Toss the cubed butternut squash with 2 teaspoons oil, 1/4 teaspoon salt, and 1/8 teaspoon black pepper. Make sure that the cubes are evenly coated with oil, and that the seasonings are distributed throughout. (You can do this in a bowl, or directly on the parchment-lined baking sheet.)
Spread the squash cubes out on the baking sheet so they aren't piled on top of each other, leaving room at the center of the sheet (this is where you will place the unpeeled half of the squash that will be the turkey's body).
Brush both sides of the remaining unpeeled half of the butternut squash with 1/2 teaspoon oil, and sprinkle the cut side with 1/4 teaspoon salt, and 1/8 teaspoon black pepper. Place, cut-side down, in the center of the baking sheet (with the cubed butternut squash surrounding it).
Place baking sheet in the oven and roast for 12 minutes. Stir the cubed squash (do not move or flip the half squash), and continue roasting for 7-10 minutes more, until cubed squash is tender and has toasty, browned, roasted spots but isn't burned. Remove the cubes from the baking sheet and set aside.
Flip your halved butternut squash over and test it gently with a fork to make sure it is done, too. If it isn't quite done to your liking, you can return it to the oven, cut-side down, for a few minutes more. Watch it closely so it doesn't start to brown too much, though, and will still look nice when used as your turkey's body.
While the squash is roasting, you can prep the rest of the salad:
Fan your lettuce leaves out on a large, round platter. (The platter I used in the photos is 13" in diameter.)
As you layer on your lettuce, sprinkle a little of the pecans, cranberries, and crumbled goat cheese throughout the layers, making sure you have plenty left to sprinkle on top.
Cut a squiggle of red pepper to make the turkey's "snood" (refer to photo in post to see how we made ours).
Scoop out little semi-rounds from the un-crumbled, remaining log of goat cheese, and gently push 1 clove into the domed, curved side of each round (again, refer to photos as needed).
In a medium bowl, whisk together all dressing ingredients.
Once the roasted squash is cool enough to handle, sprinkle the squash cubes on top of the salad. Gently lay the half-squash "turkey body" in the middle of the salad.
Place the goat cheese "eyes" on the turkey's "head," and position the triangular piece of squash and the squiggle of red pepper as the "beak" and "snood." At the bottom of the body, place the two pecan halves as "feet."
Serve salad with Maple-Balsamic Dressing.
Butternut squash size: If you have trouble finding the size of butternut squash specified, you can adjust the oil, salt, and pepper, and also the roasting time, as needed.
Gluten free mustard: While many (but not all) mustards are inherently gluten free, if you're watching your gluten intake, be sure to look for a brand that is specifically labeled as gluten free.
Ingredient amounts: Besides using slightly different sizes of squash, you can vary the amounts of lettuce, pecans, cranberries, and goat cheese that you use, to suit your tastes and your number of guests. The amount of dressing in the recipe can also be scaled accordingly.
Make-ahead steps: As described in greater detail in the post, you can cut, peel, and chop the squash a day or two ahead, and also cut the turkey's red-pepper "snood" and make his eyes ahead of time. You can also make the Maple-Balsamic Dressing up to several days ahead (re-whisking if needed before serving). Wrap/cover each element separately and refrigerate.
To work even further ahead, you can actually complete nearly the entire salad earlier in the day or the day before. You can roast the squash in advance, and rewarm it a little before serving, so you don't have cold pieces of butternut squash in your salad. (Just be aware that the squash cubes may not have quite the same toasty exterior texture when you rewarm them if they're made ahead.) You can also pre-roast, cool, and assemble your turkey's body and face ahead of time. Wrap and refrigerate him, making sure his goat cheese "eyes" aren't getting smashed by the plastic wrap. You can also lay your lettuce leaves out on the platter, and sprinkle on the cranberries, goat cheese, and pecans. Wrap it lightly in plastic wrap and put it somewhere in the fridge that it won't get smashed.