This isn't a complete list of what you can eat on a careful elimination diet, it's a list of foods I can eat. Look at plant foods relationships to see if a food not in this list would be on the careful elimination diet.

Starches: Latin roots - name (true yam), yautia malanga, batata (a starchy kind of sweet potato), taro, and cassava. I special-order these exotic roots from supermarkets in 20 or 40 pound boxes, take them home on my bicycle, peel them, cut them up and freeze them. These roots aren't constantly available like, say, potatoes are, so this ensures I won't run out of food. Also sweet potatoes, arrowroot starch, quinoa, amaranth, oca, water chestnuts.
I have a home grain mill that I grind quinoa and amaranth on. It tastes much, much better than store-bought amaranth or quinoa flour, which is pretty foul. The fats in the whole grain flours you get in the store are already spoiled somewhat, so they're bitter.

Meats: lamb, venison, rabbit, ostrich, goat

Fruits: watermelon, pear, papaya, quince, rhubarb, mango, pineapple, kiwi, cherimoya, fresh figs, currant berries, Monstera, jackfruit, persimmon, pawpaw, mamey sapote, dragon fruit/pitaya, rambutan, guanabana, passion fruit

veggies: asparagus, spinach, squash, beet, lettuce, radish, celery, okra, lotus root, watercress, cardoon. Kombu, nori, dulse and wakame, which are kinds of seaweed.

Sweeteners: maple syrup, filtered honey, beet sugar, agave syrup

fats: canola oil, palm oil, chia seeds, camelina seeds

teas: hibiscus, lavender, mullein, elecampane, gotu kola, mugwort, marigold, Indian sarsaparilla, galanga, marshmallow root, dong quai, roasted chicory root, angelica

Misc: psyllium fiber, slippery elm, wormwood. Looking for a change of consciousness that doesn't make me sick, I tried wormwood t. You'd have to have an iron tongue to drink it, it's FOUL. So I added sugar to the tea, boiled it down till it made hard candy, and swallowed it. I haven't fully investigated yet.

Spices - nutmeg, mint, vanilla beans, tarragon, saffron, mace, marjoram, savory, oregano, rosemary, basil, thyme, sage, epazote

A lot of these things can be found in health food stores or in a good supermarket.

I cut up a lot of these foods and steam them. It's quick and tasty. Name (true yam) is very good sliced and steamed.