Preheat oven to 375 degrees F. Cut top and bottom stems off butternut squash, then cut in half vertically. Scoop out seeds and rub with a tablespoon of olive oil and ½ teaspoon kosher salt. Place cut side down on a parchment lined baking sheet. Then rub onion halves and garlic with oil and a bit of salt. Place onion cut side on baking sheet, and tuck garlic cloves underneath the squash in the hollow bulb area.
Roast for 50 minutes, turning squash and onion over halfway through baking. When finished, they should be caramelized and a fork easily glides all the way through the squash.
Scoop out the flesh and add to a high speed blender, along with onion. Squeeze garlic out of the skins and add to pot. Pour in 3 cups chicken stock, then add 1 teaspoon kosher salt, cinnamon, ginger, maple syrup, and black pepper.
Puree until smooth. Stir in apple cider vinegar and heavy cream until fully combined.
Taste and the flavor should pop. If it doesn’t. Add another teaspoon of apple cider vinegar and ¼ teaspoon kosher salt. Stir and taste again until it is to your liking.