He's also allergic to potatoes.
This is a real problem during Pesach if you're Ashkenazi.
I made something I'm going to call cheese-matza strata.
Four whole matzot
8 oz shredded cheddar/mozzarella cheese mix
Olive oil spray
I sliced four onions fine and sauted them with butter and olive oil until soft and golden and then added pepper. Then I beat four eggs with a little water. I sprayed an 8x8 pan with olive oil spray, and put in a whole matza piece, which I sprinkled with hot water and then turned over and sprinkled with more hot water. I then covered the top with a thin layer of egg, then the onions and then a good amount of shredded cheddar/mozzarella mix. I covered this with another matzah, which I wet and egged on each side and then more onion and more cheese. I did this a third time, which used up the onion, and then added a fourth matzah, also wet and egged, and covered that with the remaining cheese. I put this in a 350 oven for about an hour. I cut it into six pieces, so we had seconds.
I also baked several tomatos - cutting off the top and spraying with olive oil.
First course was mesclun salad in a plain balsamic vinegar/olive oil vinaigrette. S brought walnut maccaroons. And we served a lovely Chateau Neuf that went well with the main dish.