Cook on manual high for 15 minutes. You can quick release the pressure at this point or just let it release naturally if you prefer.
Add the cauliflower. Puree with an immersion blender.
Stir in the sour cream and heavy. Season to taste. Serve immediately or let the instant pot stay on warm.
Stovetop:
Simmer the squash in the broth until tender, about 25-30 minutes. Then proceed with the other instructions.
Notes
Nutrition: Since butternut squash is a naturally starchy vegetable the servings for this soup are small. It is a great side dish. This recipe makes 8 servings. Each serving is about 6 ounces and has 7 NET carbs.Dairy-Free: Sub in full-fat coconut milk or coconut cream in place of the sour cream and heavy cream.Frozen Cauliflower: The cauliflower should be soft before you add it. If your frozen cauliflower is still firm after thawing you will need to cook it until it has softened.Prep Time: peel, seed, and chop the butternut squash up to five days ahead of time. Keep it in an airtight container in the refrigerator until you’re ready to make the soup. Or you can cheat and buy prepped squash from most grocery stores. Frozen does not have the same flavor as fresh.To Reheat: Place the soup in a saucepan and stir over medium heat. Or, place in a microwave-safe and warm it up for 2-3 minutes or until hot. It’s best to put a paper towel on top of the bowl, so it doesn’t splatter everywhere. To Freeze: Place the soup in a freezer-safe container or bag. It will last up to three months in the freezer. Defrost before reheating in the refrigerator.