I am so sorry. It is so hard to see your child in so much pain.
I had my tonsils out a few years ago as an adult, and I can honestly say NOTHING, not even hard labor during childbirth compares to the pain I was in with my tonsillectomy.
Now, I know kids bounce back WAY faster from things than adults, so I would expect you will see some progress pretty soon with your daughter.
Yet, and this is not to worry you, but give honest experience, I could not eat anything solid for 20 days, yes, 20 days, the pain was so bad. I will never miss taking 2 hours to try to eat the smallest piece of turkey and mashed potatoes on Thanksgiving, so sad.
Here are some of things I was able to tolerate and proved to be helpful. Eating crushed ice was awesome because it brought down the swelling and numbed the pain. I actually made my husband find a store that sold crushed ice instead of regular ice. Popsicles were not do-able for quite some time because the sugar and/or juice would irritate my throat.
The other thing I could easily eat and soothed my throat was chicken broth, with those slippery noodles. I am pretty sure it was the salt that soothed the area for some reason. And the noodles would just kind of slip down my throat.
Two things I would have THOUGHT would feel good, but did NOT, were any dairy products, including ice cream. The dairy causes swelling and burns the throat. Other thing that was excrutiatingly painful was bananas. The banana actually has little barbs in the fruit, and we don't normally notice, but when your throat is raw and burned from cauterization, those barbs are super painful. In fact, I was actually progressing okay from the pain, but on day 3 of my recovery, I tried to eat a banana and it ripped the scabs off the site, and I started all over with healing, and it took way longer to feel as good again as I did on day 3, I'd say it took until day 12. Such a nightmare.
I can't remember exactly, but I was in so much pain the and the tylenol with codeine was doing nothing for me really, so I started taking Advil at some point after the first 5 days when things got unbearable, even though they say it can cause bleeding. So maybe that made my recovery process longer, but at least I was able to function and feel okay when I wasn't eating.
And definitely do not let her eat nuts for a LONG time. I don't think I could eat nuts for a few months, they felt like I was swallowing thorns.
I'll pray for quick healing for your daughter!