For a simple yet flavorful veggie sandwich, try an avocado and sprouts sandwich. Mash some ripe avocado with a squeeze of lemon juice, salt, and pepper. Spread the avocado mixture on whole grain bread and top it with a generous amount of fresh sprouts. Sprinkle some nutritional yeast or sesame seeds for added flavor and texture. This sandwich is not only delicious but also packed with healthy fats and nutrients.