Question on cooked chicken diet for cats with allergic skin conditions

As some of you know, my long haired cat has some sort of allergy that
causes her to lick parts of her hind legs and feet which causes sores. The
vet thinks its a granuloma problem as she's tested negative for ringworm
and doesn't appear to have fleas (she's mainly white haired).

She's currently on Triamcinolone (1 mg/day). Prednisolone seemed to stop
working as she probably built up a tolerance to it.

Anyway, I'm trying to wean her off of Fancy Feast. Removing wheat glutens
and corn from her diet by using Hills Prescription Diet d/d didn't work.

If I switch to a diet of cooked chicken, what chicken do I buy?
I was looking at the Perdue skinless and boneless breast cuts in the
supermarket which are 99% fat free. It says "no additives" and "mininal
processing".

I was thinking of giving her this in addition to Dermcaps from Drs. Foster
and Smith. It's a vitamin supplement that's high in Omega oils, which are
supposed to heal the skin for cats with allergic conditions.

Comments and any advice would be appreciated. I know there's natural cat
foods out there but I'm worried about going with a small food manufacturer
out of fears of quality control. Some say because they're smaller
distributors, they have better control, but I'm still a little leery.
If only Purina would use their clout, and develop better and more extensive
lines of food. Every time they introduce a "natural" food, I get excited,
only to look at the ingredients and see the same byproducts and mixture of
every protein under the sun.

Sorry to digress. Has anyone had luck with the cooked chicken diet?