We just did this 2 weeks ago (3 1/2 little girl), as did a friend in my daughter's preschool class. Both girls had the whole enchilada, tonsils, adenoids & ear tubes.
For us the first few days were rough. She does not like jello, so I had pudding, popsicles, ice cream, yogurt, juice, applesauce, anything soft I could think of. The first day she didn't want anything to eat but drank ice water, and threw up a few times. I thought it might be from her medicine, but my doctor said it could also have been from the anesthesia.
The next day she slept a lot, and did not want anything to eat, but drank when I offered her water or juice. It took most of the day to get her to drink a tiny juice box though. By mid day she perked up a little after her nap and she had some soft food-she wanted mac & cheese, so I gave it to her. Her doctor said that she could have anything she wanted and could handle. So she ate mac & cheese, yogurt, pudding, and apple sauce for about 2 days before she started asking for pizza.
She recovered very quickly. Surgery was Thursday, by Saturday she was playing with her big sister, and Monday she was crushed not to be able to go to school, but she was also still waking up in the night crying and needed her medicine so I didn't think she should go. She hated taking her meds so I mixed regular tylenol with her tylenol & codine meds and that went down better. (I checked with the doctor first though).
Tuesday she wanted to go back to school, so I let her, but let them know to call me at any point to get her. I honestly expected to get a phone call at 10:30 or so to get her, but she had a great day back. Since then she has been going to school and that was also the last night she woke up at night.
She was much quieter than normal and her voice is pitched differently. She can hear better, and her breath was awful at first, but is fine now. All in all we had a rough 4-5 days, but she is fine now-14 days later. Her doc recommended no school for 7 days, but said to play it by ear.
That being said, that was not the case for my friend's little girl. She was miserable for the full two weeks, and is just now back at school. She only ate cold frozen things and was one the full strength meds for 10 days.
So I was pretty lucky my little one healed very quickly. I was really nervous about recovery beforehand as I had heard lots of scary stories. Push the water or juice and they heal faster, or at least seem happier. I let her call the shots with food for the first week and only this week have started pushing that she eat what we are having for dinner, but I have not made anything too crunchy lately. I am still putting softer things in her lunch so she always has those things to eat. I also avoided cold cereal at breakfast for 2 weeks. But she doesn't seem to need any tylenol at night and sleeps just fine now and is a much happier little girl. She had the surgery because of drainage issue. Her adenoids were huge and blocked off the ear drainage and so her ears filled with fluid. They did not get infected, but she could not hear well. We tried months of allergy meds, but they had no major affect. She has not had her allergy meds since the surgery, but does not seem sniffly or congested for the first time in a really long time!
I wish you all the best.