Preheat the oven to 375°F (190°C). Line a baking sheet with parchment paper.

Place the halved and seeded acorn squash on the prepared baking sheet, cut-side down. Pour enough water into the baking sheet to cover the bottom.

Roast the squash in the preheated oven for about 40-45 minutes, or until it is tender when pierced with a fork. Remove the squash from the oven and let it cool slightly.

Melt the unsalted butter in a large pot over medium heat. Add the chopped onion and carrot and sauté for 5-7 minutes, or until the vegetables are soft and fragrant.

Add the minced garlic to the pot and sauté for an additional minute.

Scoop out the roasted acorn squash flesh from the skin and add it to the pot with the sautéed vegetables. Stir well to combine.

Pour in the low-sodium chicken stock and bring the mixture to a boil. Reduce the heat and let the soup simmer for about 15 minutes.

Remove the pot from the heat and let the soup cool slightly. Use an immersion blender or transfer the soup to a blender in batches and blend until smooth and creamy.

Return the blended soup to the pot and stir in the half-and-half, ground nutmeg, ground cinnamon, salt, and pepper.

Heat the soup over low heat for a few minutes, stirring occasionally, until it is heated through.

Ladle the soup into bowls and serve hot, garnished with fresh herbs, croutons, or a dollop of sour cream, if desired. Enjoy!