Set a large pot or Dutch oven over medium-high heat and add a generous drizzle of oil. Add the onion, carrot and celery and cook for 4-5 minutes, until starting to soften. Add the turkey and cook, breaking up with a spoon, until the meat is no longer pink. Add the cilantro (if you like, save some of the leaves for garnish), garlic, chili powder, cumin, and some salt and pepper and cook for another minute.
Add the stock, squash, apple, tomatoes, coconut milk and black beans. Bring to a simmer and cook for 30-45 minutes, until the squash is tender and the chili has thickened. Season with more salt, if it needs it. Serve right away or cool and refrigerate overnight, then reheat the next day. Serves 6.