S.C.
My DD suffered with food allergies since she was two weeks old. She was allergic to wheat, eggs, corn, dairy, all nuts, soy, and at some points grew allergic rice, apples, and other foods that we feed her too often. When that happened we would need to stay away from that food for 6-12 months.
We fed her things made from Quinoa, Millet, and other such grains. Though she was allergic to wheat, she could eat cake/cup-cakes I made from Spelt and there is bread that is sold at Whole Foods and sprouts that is made from Spelt.
Btw, the allergist I went to is Dr. Rao and he sells an (non-rx) enzyme that helps digest foods so that she can eat stuff that she is still midly allergic to. Since she has/had so many allergies, we had to eat some of the items so the enzyme helped there.
Good luck and PM me with any questions if you want. Btw, my DD has out-grown many of her allergies.