There was a long thread on this a while ago, but I'm not the best searcher
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My kids like beans and rice (I do homemade baked beans with the little white beans from scratch in the crock pot, not hard at all), lentils & rice, falafal (not hard to make especially with canned chickpeas), stir fry tofu, BBQ tofu, hearty veggie soup with chickpeas over couscous, quiche, red dragon pie, can't think of anything else now. By the way, a lot of things you can do with ground beef you can do with lentils (red dragon pie, sloppy joe, meatballs, etc).