Setting up Tips for income already received to deduct taxes

We have a scenario where employees receive tips that are paid on the day the employee works so the amount of tips received does not need to be paid with the normal payroll but they do need to report the amount for withholding taxes.  I did not see a way to use Tips as an earning code that would not increase the amount of the net pay.  Has anyone else had a similar scenario or have a recommendation on how to handle the tips?