Ideas on identifying allergies/hypo-allergenic food

[Delirium]

Alrighty, Sneaky, my beagle, has chronic otitis. I've known this since I got her in April. However, i'm attempting to find out what's causing it. Today, we got her vet test results back and they found no bacteria in her ear. The assumption now is that the cause of her otitis is either an allergy to something or a hypo-thyroid.

Now since she's not a good looking candidate for thyroid, i'm going to tackle the allergy question first I think. However, my vet, in true vet form, recommended Hills or Medical hypo allergenic foods to do a trial on. The problem is, i'm a little skeptic about Hills and know why vets recommend the foods they do. Medical I can't comment on and i've not yet had opportunity to check the label on the bags. So, any ideas on what the best hypo-allergenic food to go with is? I'm thinking that I want to go straight to plain jane rather than weed out individual food types one by one. I'll go straight to hypo-allergenic, see if her otitis stays away, then start reintroducing foods to see if I can catch the bugger that does this to her. If given the option, I don't want to sacrifice quality for this and Hills scares me. Thoughts?

I'm open also to home cooked food i'm convinced that that's the best option.

Would love some share experience if you've got it.

Dee