Butternut Squash Soup

Name: Butternut Squash Soup
Ingredients: 2 Tbsp. vegetable oil, plus more for greasing; 2 butternut squash (about 4¾ lb. total), halved lengthwise, seeds removed; 2 cups thinly sliced white or yellow onion; 1 Tbsp. light brown sugar; 2 tsp. minced fresh ginger; 2 garlic cloves, coarsely chopped; ½ cinnamon stick; 5 cups (or more) low-sodium chicken broth or vegetable broth; Kosher salt, freshly ground black pepper; Chopped fresh parsley for serving