Daughter and I both have celiac disease, so are gluten-free. We also have several auto-immune diseases each, so use the auto-immune protocol, or AIP, diet as a guide-line. We aren't sticking to it strictly anymore -- it's meant as an elimination diet, to be followed for a while and then you start re-introducing foods slowly, one at a time, until you've figured out what you can and can't eat. We can't eat a lot of seeds, including quinoa and buckwheat, but can eat white rice in small amounts, and we can get away with oatmeal if we only have it once in a while. So I've stocked up heavily on white rice, and have some oatmeal, too. We also can manage potato once in a while, so have instant mashed potatoes on hand. I've also got some canned sweet potatoes in the pantry, although I prefer fresh as I don't like all the extra sugar in the canned ones.
Our other starch is cassava flour; I'm not heavily stocked up on that, but we do have some. And we have some coconut flour, but use it sparingly as it seems to bother my stomach.
We can't handle much tomato, and NO peppers (bell, chili, etc.). Peppers really do a number on my daughter, especially.
Beyond all that, our preps are fairly normal. I'm emphasizing canned and dry foods, even though I have three freezers, as I want stuff that won't spoil if the power goes off -- I have canners (two) and plenty of jars and lids, but it would take quite a while to can that much stuff. We have a lot of canned veggies and meat, and some canned fruit. In addition to quite a lot of white rice, we've got some dry beans and other legumes, though we have to eat those a bit sparingly.
As long as we can feed them, we've got chickens for eggs, and dairy goats for milk (and a little meat now and then). And we've got seeds to plant next year's garden, and another year after that. As long as we are left alone, we should be good for food for quite a while.
There are a couple of keys to seasoning an other-wise bland diet such as we have to eat. Meat broth helps a LOT. I don't have room to store much in the way of canned broth (with limited space, I've chosen to stock up on canned gluten-free soups instead -- check soup labels, as most of them are thickened with wheat even if they don't have pasta or barley in them, but Progresso has some that are gluten-free), but I do keep some, and can make more if needed. Butter and cheese are also good additions -- once in a while I'll make rice and cheese, similar to mac and cheese. Mushrooms, if you like them, are good for adding flavor to things. Salt, of course. And some seasonings. You probably don't want the mixed spice seasonings, as some of those will have gluten in them. We can't use any of them because of the peppers that are almost always included. So I have large containers of single herbs, such as thyme and sage. Given our climate (hot and humid in the summers), it would probably be wiser to have several smaller containers, so I don't have all of a large open container exposed to the atmosphere.
You can get gluten-free stuff like crackers and bread -- some of them are really quite good now. But they are very expensive for what you get, so I don't keep any of that on hand. Once in a while I will make something from scratch.
Hope this helps. Having to make a major change in your diet is probably one of the hardest things to do, and it sure does complicate keeping stored food. You might be able to trade your wheat and other things you can no longer eat for someone else's white rice.
Kathleen