One Button splitting two items

[pdx209]

e.g. Jack and Coke is $9.00 - we want single button that splits the Jack and Coke - reciept would show Jack $7.00 / Coke $2.00 - Assume/Understand this can be done with modifiers, just want to eliminate a step (per bartenders) - Thank you in advance!

[VanKalkerFarms]

Currently, there is not a way to do this in one step.