Preheat oven to 425 degrees Fahrenheit (220 Celsius).
Prepare 2 baking sheets by lining them with aluminum foil (optional but makes for quick clean up)
Place the butternut squash, sweet potato, and apple on one of the baking sheets and drizzle with ½ tablespoon of olive oil. Season with ½ teaspoon salt, and ¼ teaspoon pepper. Toss to coat.
Place the prepared onion, carrots, celery, and garlic on the second baking sheet. Drizzle with ½ tablespoon of olive oil, and season with ½ teaspoon salt, and ¼ teaspoon black pepper. Toss to coat.
Add the baking sheets to the preheated oven and roast for 25-30 minutes, or until the vegetables are lightly caramelized.
Remove the baking sheets from the oven and transfer the sweet potato and apple to the baking sheet with the carrots and celery. Set aside.
Return the butternut squash back into the oven and continue to roast for an additional 20 minutes, or until tender and can easily be pierced with a fork.
Remove the squash from the oven and allow to cool.
Once cooled, use a spoon to scoop out 1 half of the cooked butternut squash and place it in a high-speed blender.
To the blender, add in 1 cup of the chicken broth, ½ cup of the white wine, ¼ cup of half and half, half of the roasted veggies, 1 teaspoon salt, ½ teaspoon black pepper, and a pinch of freshly grated nutmeg.
Cover and blend on high until smooth and creamy.
Pour the blended soup into a container (if making in advance), or stockpot for reheating, and continue the process with the remaining ingredients.
Heat the soup gently over medium/low heat, spoon into bowls and garnish with pepita seeds if desired.
Serve hot.