cordova.plugins.SecureKeyStore is not ready when onDeviceReady fires

I am trying to access cordova.plugins.SecureKeyStore, after the cordova onDeviceReady event fires, but I am finding I get:

"Unhandled Promise Rejection: Type Error: undefined is not an object (evaluating ‘cordova.plugins.SecureKeyStore’)

I would have thought onDeviceReady would be an indicator that ‘all cordova APIs are available’ as per docs, but it seems this does not include plugins? Is that correct?

How can I create an eventListener that will listen for when cordova.plugins.SecureKeyStore is ready, and execute a function as a callback on that event?