Preheat the oven to 400 F (205 C). Cut the butternut squash in half lengthwise. Use a spoon to remove the seeds.

Place each squash half on a parchment-lined baking sheet with the flesh side facing up. Bake for 50 to 60 minutes at 400 F (205 C).

Peel and quarter the onion. Cut the apple into large chunks. When you have 20 to 25 minutes of baking remaining with the squash, place the onion and apple next to the squash to roast.

The squash, onions, and apple chunks are done when they soften and start to brown. Let the squash cool to room temperature or cool enough to handle.

Peel the skin off the butternut squash, cut into large chunks, and place them in a medium pot along with roasted onions and apple chunks.

To the soup pot, add the low-sodium vegetable broth. Turn the heat to medium-high and bring to a gentle boil. Reduce heat and simmer partially covered for 5 to 10 minutes.

Use an immersion blender to blend smooth. Add ground nutmeg and plain unsweetened soymilk, and continue to blend for a few more seconds.

Dish up the soup and top with fresh chopped sage, pistachios, and salt and pepper to taste. Enjoy!

Leftovers keep well in a covered container in the refrigerator for up to four days. You can also freeze this soup in freezer-safe containers for up to four months.