The call stack pane can be used to view the build call stack while stepping through a build.  It is accessed by choosing View | Other Windows | Call Stack on the menu bar.

 

 

The current step is displayed at the top, followed by each parent step on the build call stack.  Double-click on a step (or select and press Enter) to navigate to that step.  The call stack is automatically refreshed when the build pauses or stops at a breakpoint and can be manually refreshed by choosing View | Refresh on the menu.