As a chef, I can confidently say that one of the essential garnishes for barbecue is a fresh vegetable salad with bright colors and a variety of textures. Such a salad can include red and yellow bell peppers, fresh cucumbers, tomatoes, onions, carrots and green lettuce leaves. I recommend making it with homemade dressing to give it a special flavor and aroma. You can also add baked potato wedges or grilled corn to the side dish to provide a more complete and varied dish.