Pack a few pieces of LF string cheese, or a peeled hard-boiled egg or two, and a fruit. This can hold you over from breakfast till lunch, with no problem, then you have your sandwich. I'd make a wrap on a WW tortilla or use a WW pita, stuffing that bad boy with tons of lettuce and grilled veggies as well as the protein (ham, turkey, chicken, etc.). You could also bring baby carrots and salsa or hummus as a dip. Add a fruit and a drink, and you're good to go.