Kate Hudson signed up with Michael Kors' campaign 'Watch Hunger Stop' - launched in 2013 - and the pair have designed two limited-edition styles of the Bradshaw watch.
Every sale of one of these Bradshaw 100 watches will enable 100 children in need to receive a nutritious meal through the United Nations World Food Programme's initiative, and Kate "can't think of anything more important".
The actress said: "I'm proud to join Michael Kors in this global effort to end hunger. As a mother, I can't think of anything more important than raising a healthy and educated generation of children, and WFP's School Meals Program is committed to exactly that. This is a cause that I'm eager to be a part of because I believe we can all make a real and significant difference."
Michael said he's "excited" to have Kate on board who's bringing a "can-do attitude".
The designer said: "I am so excited to have Kate Hudson join me in the fight to ensure that no child anywhere in the world goes to bed hungry. Not only does she have a unique star quality but she also brings an incredible amount of generosity and a can-do attitude to a cause that is extremely important to me personally."
The watches will be available exclusively in Michael Kors stores worldwide and on michaelkors.com in the US from October.