extensions/winrm/v1/enableWinrm.ps1 (3 lines of code) (raw):
$cert = New-SelfSignedCertificate -DnsName (hostname) -CertStoreLocation Cert:\LocalMachine\My
winrm create winrm/config/Listener?Address=*+Transport=HTTPS "@{Hostname=`"$(hostname)`"; CertificateThumbprint=`"$($cert.Thumbprint)`"}"
winrm set winrm/config/service/auth "@{Basic=`"true`"}"