From the question, you suggest this is an unfamiliar food for your chickens. I would only cook and offer small amounts the first couple of times. Once they decide it's good food, they'll be happy to eat more.
A friend gave me some corn on the
cob which had actually started sprouting. Those chickens have never had corn on the cob. Two hours later, it was still sitting there. I expect that will change soon
enough. In contrast, if I showed up with Russian Kale, it would be gone in less than 5 minutes! They know Kale and know they love it!