If you like beans you can make chili (no meat needed) , which is really filling, or I make bean salads,
Just a can of beans, kidney or great northern or what ever type you like (rinsed) a little mayo mayo, any herbs or spices you like . I use minced onion or celery, a little mustard. You get the idea, my husband is a veg too, so I make him lunches everyday and try to switch up the flavors of the bean salads often.
And as was mentions pasta salads are yumm too.