Tuna Salad Sandwich
Tuna's a lunch staple for a reason -- it's inexpensive, healthy, easy to prepare and tastes great. But it certainly doesn't have to be boring. Try serving the tuna salad on a croissant, in a wrap or in a pita pocket to steer away from the standard sliced bread. To the salad itself, add chopped celery, pickles, tomatoes or green olives for a little color and flavor.
You can even swap out the traditional mayonnaise for other tasty options, like Greek yogurt or sour cream, which will create entirely new flavor combinations while still holding the salad mixture together. Top off with cucumber or fresh tomato slices for a delicious lunch that's packed with protein and budget-friendly.