Policy for monthly team lunch to employees who perform well

Hi ,
Every month, we give team wise lunch to employees who perform well. I need policy for the same. Could you please help me with the same?

Hi,
You are appreciating employees who perform well regularly in a defined frequency.
This is fine, you can either circulate the same through a circular/email or a general notice specifying the criteria how are the employees being judged for this appreciation.
If you have HR manual broadly laid out, you can mention in that also about time to time R & R (rewards & recognition) or appreciations being done.

Hi
Can someone share me the format for the same?