My brother is a vegetarian who doesn't eat vegtables, and he does fine, so you dont have to panic. Find one thing she likes, I would recomend trying potatoes, corn, beans, cheese, sandwiches ect. Then find 10 different ways to cook it which each provide different nutrition, this might lead to her mind being opened to the other ingrediants in the food, and keeps her healthy untill her palat matures with age
corn- corn fritters, potato/corn pancakes, roasted corn, corn soup
beans- bean dip for chips, bean mixture for tacos, black bean soup, beans and rice
I dont know if this will work for your daughter, but it worked for my brother, he started out only eating white foods (literally) and is now quite the chef and eats more different kinds of food then I do.