Of course not! Do yourself a favor, though, and try this recipe as it is first, then feel free to swap in other fall and winter veggies. For example, use diced carrots, rutabaga, parsnips, or multicolored potatoes instead of the squash, and use chopped spinach, kale, or collard green leaves instead of the chard. (But don't use kale or collard green stems; they won't get tender like chard stems do.)