Easy Vegetable Bolognese with Spaghetti Squash

Name: Easy Vegetable Bolognese with Spaghetti Squash
Ingredients: One 3- to 4-pound spaghetti squash; Extra-virgin olive oil, for the pot and drizzling; Kosher salt and freshly ground black pepper; 4 cloves garlic, roughly chopped; 1 large carrot, cut into chunks; 1 celery stalk, cut into chunks; 1 large yellow onion, roughly chopped; 1 pound cremini mushrooms, quartered; 1 large zucchini, trimmed and cut into chunks; 1/2 cup milk; 3/4 cup red wine, such as pinot noir; One 28-ounce can crushed tomatoes; 1/2 cup fresh basil leaves, torn, plus more for serving; 1/2 teaspoon red pepper flakes; One 2- to 3-ounce piece Parmesan rind plus freshly grated Parmesan, for serving