Good day Everyone,
After all our hard work in the past few [time], the company has decided to treat the entire [Department/company/team] out for lunch. This is to extend their gratitude and appreciation for our efforts in the company.
The said lunch will take place in [venue] on [date]. It will start around [hour] but please arrive slightly earlier to make sure everyone is settled down before the food arrives.
Here is a list of food to be served:
[list of things on the menu]
We hope to see you all there!
Thank you and have a great day,
[Position in the company]