In a saucepan, over medium heat, place frozen butternut squash, chicken broth, chopped onion, and garlic.
Bring to a boil. Add salt, pepper, and sage. Cook for about 10 minutes.
Using your immersion blender, blend the soup until it is smooth. You can also blend it in a traditional blender.
You will need to return the soup to the pan and add milk or cream. Serve and enjoy.