Quick Start guide Prerequisites ngrok .NET Core 3.0 runtime installed Need Azure Account with Azure Speech resource Need subscription Key and region from said Azure Speech resource Startup Open TranscriptionBlogPostDemo.sln Open Project Properties for TranscriptionBlogPostDemo Under Debug tab take note of the port number (may want to disable ssl for the sake of simplicity) in command-line execute ngrok http --host-header="localhost:<port_number>" http://localhost:<port_number> Link Nexmo Voice application to ngrok tunnel Change BASE_URL in VoiceController.cs to the base url of your ngrok tunnel (excluding the http://) In Transcription Engine set up the Speech Config with your subscription key and region. Start in IIS express