1. Preheat the oven to 400°F (200°C).

2. Cut the acorn squash in half lengthwise and remove the seeds.

3. Place the squash halves on a baking sheet, cut side down.

4. Roast in the preheated oven for 45-50 minutes, or until the squash is tender.

5. Remove the squash from the oven and let it cool slightly.

6. Scoop out the flesh of the squash and set aside.

7. In a large pot, heat some olive oil over medium heat.

8. Add diced onions and minced garlic to the pot and cook until onions are translucent.

9. Add the roasted squash flesh to the pot and stir to combine with onions and garlic.

10. Pour in enough chicken or vegetable broth to cover the squash mixture.

11. Bring the mixture to a boil, then reduce heat and let it simmer for about 10 minutes.

12. Using an immersion blender or regular blender, puree the soup until smooth and creamy.

13. Return the soup to the pot and stir in 1% milk until well combined.

14. Season with salt, pepper, and any other desired seasonings.

15. Simmer for an additional 5 minutes, stirring occasionally.

16. Serve hot with crusty bread or croutons.