Hello,
I have heard of chicken keepers claiming to have success with cooked navy beans.
There could be many reasons why your hens are not laying other than feed. It could be the weather (too hot, too cold), molting season, a constant scare, parasites, or perhaps they find their laying boxes not to be comfortable/private enough. Replacing their box bedding and placing a fake egg may encourage egg production. Also, do your hens free range? From my experience, if I do not find eggs for more than four days, I have to go for an egg hunt in their free range area. They sometimes lay in a secret spot that you need to discover.