For the Pi Rho Maniacs, I'll take the last spot for this challenge. I already had one in mind!
For the challenge, one of my favorite "throw it together" sandwiches has now been memorialized in this recipe: http://www.justapinch.com/recipes/main-course/sandwiches/tangy-hummus-gyro.html
The qualifying ingredients are: hummus, gyro slices (lamb), kalamata olives, feta, cucumbers, and red onion. Inside a pita, of course!