I went to a conference over the weekend at a venue I've been to before. This time I managed to get the caterers to understand the problem. This was the guidance I gave. I have never been so well looked after....
It's salicylate hypersensitivity, which you may not be familiar with.
no pepper, spices or herbs. Most fruit is out and quite a few vegetables.
Banana and golden delicious apple are okay as are chips, baked potato, cabbage, peas, sprouts, lettuce, leek and celery.
All meat, dairy and fish is fine, although fish is especially good.
Small amounts of chocolate as in cake or pudding are fine.
Only drinks are water or decaffeinated coffee. Nothing else.
The general principle I work to is that sauces and pies are dodgy. Plain meats, battered fish etc are okay.