error: could not build Objective-C module 'Quick'

Running my Quick and Nimble tests in Xcode and I am now getting this error out of the blue.

Build/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/Quick.build/module.modulemap:2:19: error: umbrella header 'Quick-umbrella.h' not found
  umbrella header "Quick-umbrella.h"
                  ^

error: could not build Objective-C module 'Quick'

How can I fix this?