Can you use this as a way to teach your daughter to cook? She needs to research recipes, plan meals, cook, learn to make extra for the next day etc; Also nutrition- the importance of vitamins and minerals, what to eat to get a good range...
Your daughter might be on to something- a plant based (vegan but not junk food) diet is now proven to be the healthiest way to eat, partly due to the nasty drugs etc that are found in meat and eggs and mercury in fish. (Read The China Study, Nutritionfacts.org, How Not To Die..).
We haven't fully committed to this yet though - as it's hard to change - but as a family we eat more variety of fruit, veg and beans, nuts and seeds.
A few recipe books to try: forks over knives, oh she glows... think great burgers, hotpots, chillis and curries/stir fries, tex mex...
Vegans can get everything they need except B12 (many meat eaters are deficient on this too BTW) but as with meat eaters, only if they eat non-processed food - eating junk food albeit vegan is not necessarily healthy! And you may not want to mention this but Quorn isn't actually vegan BTW, it contains egg white but we love it!
Get good quality B12 supplements - Solgar, Biocare...