GST on subsidized Food provided to employee

We run canteen in our Plant where Food is provided to employees at subsidized rates. There is service order issued to out side contractor who prepares food in our premises. We know GST is applicable on the amount paid to contractors.

But is GST applicable on the amount collected by the company from employees ? 

Answer ; GST is payable on open market value i.e. price a which Company is paying to contractor even if Company recover less amount from employees

Refer Also Pay GST on Recovery of Food expenses from Employee for Canteen : AAR