funny you should mention that... I just made a really good spinach quich for my ladiies group
I used my favorite recipe, developed between my sis and I. Instead of putting any meat in it, I defrosted 10 oz. of chopped spinach, squeezed it REALLY dry in a dishcloth, and added that. Got rave reviews.
You can use about any combo of cheeses you like. I really like myzithra, havarti and Swiss... mix it up to your own liking. The cheese blends at the store (or Trader Joes) that contain Swiss cheese are always good.
I just poured it into a 9x12 baking pan (sprayed with Pam) and made it crustless for less carbs.