Normally when cooking for vegetarian friends I focus on making the food interesting, since a one-off meal isn't going to throw them too much. However, we will be having a vegetarian stay with us for several weeks, and I am concerned that if I don't deliberately plan meals that provide what we'd normally get from meat in some other way it will be a problem over that length of time.
I am aware of the need to provide iron and protein, and that cheese, nuts and spinach are good things to try to include. I'm hoping to avoid soy and tofu, as my wife and I don't like either, and any meat imitation products are out since it's the taste/texture that's an issue, not principles. What else do I need to bear in mind / try to include? Any tips welcome.