You can serve a few different courses that should not cause too many issues with your tonsils - or lack there of!
Open with a pureed type of soup - like a butternut squash, tomato Parmesan basil, or cheddar broccoli. I remember when I had my tonsils out I was a bit mucus-y afterwords so if you are too, then opt for a non-dairy soup instead, like a summer squash veggie soup. Remember not to make anything too spicy because it might irritate your throat. Allow your guests to add extra pepper/other spices if they want to their portions.
For the main course, you mentioned that you'd be fine eating macaroni and cheese, so why not make an adult version? Make a cheese sauce using a blend of cheeses, add in some panchetta otraditionalal smoked bacon, sauteed mushrooms and onions and some peas and serve with grilled chicken breast (which you can either eat little pieces at a time, or omit from your portion).
For dessert, of course ice cream can be on the menu, so you can try to fancy it up by getting a great gelato (Italian ice cream) from your local grocery store or italian restaurant and serving it with cappuccinono (which will feel nice on your throat).
Hope dinner works out well, and feel better!