I just had to answer his one! It brought back memories of my son at that age.
There are two issues here: 1)what and 2)how much your daughter eats.
1. My son had been a great eater up to this point- loved everything, then suddenly stopped eating many things, including meat or chicken. At this age their taste buds are changing/developing, so I let him choose (from healthy selections). I had read about a study done on toddlers, and it concluded that given a healthy selection of food, they would choose not only a balanced diet, but would eat more of the things that they needed, if they had any kind of deficiency.
I checked this out with his pediatrician, because I was concerned about his diet (he had become vegetarian by age 3). The doctor asked what he ate, and when I listed his limited food list, the doctor said it was very healthy and better than what most kids his age ate. (It was something like "yogurt, pasta, veggies, fruit, eggs, grilled cheese and peanut butter and jelly sandwiches."
2. This same study said the toddlers also would eat as much as they needed, and would naturally stop (or not eat) when they were full. One of the causes of our overweight society is that we are made to eat as children, and we teach our bodies to eat when we are not hungry. We also overestimate how much food toddlers need.
Dinnertime is probably the most important "together" time for a family. It's so important to enjoy that time and not have it leave memories of tears and tantrums.
So my advice to you is to let her choose from what is served for dinner (I always tried to include at least one thing my son liked.) The rule was, you can eat whatever you want from what is offered. When he got older, this was amended to "...or you may make your own dinner." He learned to cook some simple things so when I was making something he really didn't like, he would cook along side me, and we would still all eat together as a family.
(I should mention that a related rule was that when we were guests at someone's house, he had to choose from what was on the table, even if there was nothing he would eat. In that case, he would put a small amount of food on his plate and politely try to eat a ittle.)
This ended up longer than I intended, but it worked so well for us once I stopped "making him eat" I wanted to pass it on.
Good luck!