Healthy Creamless Roasted Butternut Squash Soup

large butternut squash, sliced in half and seeded

large carrots, peeled, roughly chopped

stalks celery, roughly chopped

large onion, peeled and diced

garlic, peeled and minced

vegetable stock, homemade or store bought. fat-free and low-sodium

teaspooon coconut oil, divided

salt and pepper,

coconut milk, garnish (optional)

basil, chiffonade, garnish (optional)