Melt coconut oil over medium heat in a large pan. Saute onion until soft. Add squash and remaining ingredients. Bring to a boil. Simmer until squash is tender.
INSTANT POT INTRUCTIONS: Set Instant Pot to Saute. Melt coconut oil. Add onion, and saute 3 minutes. Add remaining ingredients. Pressure Cook for 10 minutes. Quick Release the steam.
Puree the soup either with an immersion blender or by carefully transferring it in small batches to an upright blender. Be careful when handling the hot liquid!
Peeling butternut squash is easiest if you first cut it into long, thin wedges. Then, laying wedges on their sides on a cutting board, cut away the skin with a sharp chef's knife aimed down toward the cutting board.
Leftover butternut squash will keep nicely sealed in an airtight container in the refrigerator for a few days or in the freezer for a few months. Be sure to leave some room in the container for expansion if you're freezing it.