I agree with you there, those Mozambique chickens were quite thin on breast meat as I recall, and they were quite small birds.
I use butterflied chicken breasts for several dishes, that might work, although off the bone, as I'm sure you're aware, can end up tasting a little dry if you over do it.
Anyhow I'll have a go to and we can compare notes!
I've been looking for a recipe for this for ages, but the info I got in Africa varied so much depending on who I heard it from, interestingly this recipe contains all the ingredients that appeared in every the version I heard about, combined. Problem was each individual method I was given missed out a key ingredient, possibly deliberate for all I know!