Roasted butternut squash with mustard vinaigrette is a flavorful and vibrant side dish that showcases the natural sweetness of butternut squash. The squash is roasted until tender and caramelized, then drizzled with a tangy mustard vinaigrette. The vinaigrette is made with Dijon mustard, apple cider vinegar, olive oil, and a touch of honey for balance. This dish is perfect for fall and winter gatherings, and pairs well with roasted meats or as a topping for salads.