How do I calculate the heading to steer in this example?
You are holding 215 by compensating for a crosswind using 5 degrees of heading change.

The opposite of 215 is 035.

You must compensate by holding 5 degrees of heading change past 035.



Presumably, the fact that you're 30 minutes flight time away from the VOR when you turn gives the pilot sufficient time to reestablish themelves on course. Thanks @MichaelHall!