Ahhh! So many.... I am a failed vegetarian many times over, but sandwiches are one area I succeed in!
Some of my favorite items include - avocado, hummus, flavored cream cheeses, sprouts, cucumbers, portobello mushrooms, tomatoes, cheese, spinach, basil, olives, the possibilities are endless! I am a big fan of veggie paninis (tomato and mozzarella... yum, yum!). Going in the non-vegetable direction of vegetarianiasm, there's always peanut butter, jelly, nut butters, or nutella!