Preheat your oven to 425 º. Slice the ends off of the butternut squash. With a flat surface on the bulb end, stand the butternut squash on end and carefully slice it in half lengthwise. Scoop all the seeds and strings out of the center. Brush the flesh with olive oil and season with salt and pepper. Roast for 50-60 minutes
Prepare the onion and garlic. Slice the onion into large chunks and cut the top of the garlic clove off. Place the clove into a tinfoil cup and place in the center of a small cooking sheet. Place the onions around the garlic. Drizzle oil onto garlic clove and onions. Place in the oven with the squash on the lower level. Bake for 10 minutes. Pull it out, add the cashews in with the onion, bake for another 10 minutes. Pull out and let the squash finish baking.
Once squash is finished (you will know when it is tender enough to stick a fork through the thickest part). Set it aside and let it cool for a bit. Once the butternut squash is cool enough to handle, use a large spoon to scoop out the flesh and transfer to a high speed blender or food processor. You can also use a knife to rid of the squash skin if needed, just try not to waste any.
Add the onion, cashew, and 3-4 roasted garlic cloves. Add in seasoning, broth, coconut milk. Blend on high until the soup is thick and creamy. Feel free to add more broth/salt/pepper if needed to get desired thickness and taste. If you are using this as a sauce you will want to keep it thick.
If the soup is still hot to your liking, pour the soup into bowls and garnish with pepita seeds and a light drizzle of coconut milk. If you need to reheat it a little, add to a sauce pan and put on low heat for about 5 minutes, stirring often. Microwaving the individual bowl, covered, for 2 minutes will also work.Use the leftover garlic cloves on toasted bakery bread, chopped into eggs or any other recipes you are cooking. You can also freeze it in a small bag.
Notes
*you won't be adding the entire bulb to the soup, rather taking a few cloves out of the bulb and saving the rest for other recipes. You can also just roast a few cloves with the onions if you would prefer.