The egg salad sandwich is a classic and satisfying option for a veggie sandwich. It's made with hard-boiled eggs, mashed with mayonnaise, mustard, and seasonings. Layered between two slices of bread, this sandwich is creamy, flavorful, and packed with protein. You can add additional veggies such as lettuce, tomatoes, or sprouts for extra freshness and crunch. It's a great option for a quick and easy vegetarian lunch or picnic.