If you don’t have all the items or dishes you need to serve then you can ask for assistance to fill one of the orders per row in your Chillout Event.
Simply tap on the item and then you can either select “Serve” if you have all the required items or “Ask For Help” if you need help. A request will go out to your friends, Chefs Club members, and other Tasty Town players to donate the required item or dishes.

Once you have received help from another player you will be notified that the order is ready to serve. The player's avatar will appear on the item that they have helped you with.

You can also help other players fill orders for their Chillout Events and as well as receiving a Horseshoe you will also receive Gold and XP when you donate items or dishes.