Preheat the oven to 400 degrees F.

Chop the tip and tail off the butternut squash and halve it length-wise. Scoop out the seeds and innards. Drizzle with oil and sprinkle with sea salt. Roast cut-side down 50 to 60 minutes, or until flesh is very soft when poked with a fork.

Spread the pecans on a baking sheet and roast for 3 minutes while the squash is roasting, or until golden-brown and crunchy. Remove from the oven and set aside.

Once the squash is cool enough to handle, scoop the flesh into a high-powered blender, discarding the skin.

While squash is roasting, sauté the leek. Add the coconut oil to a skillet and heat to medium-high. Add the leek and sauté, stirring occasionally, until leek is bright green and softened, about 3 to 4 minutes.

Transfer sautéed leek to the blender along with 2/3 cup of the roasted pecans, coconut milk, broth, sea salt, and nutmeg. Blend on high until completely creamy and any lumps are out. Taste soup for flavor and add more sea salt if desired.

Serve with chopped green onion, pesto sauce, and the remaining roasted pecans.