Adding ticket URL to SendEmail component in Workflow

For various reasons, we are using workflow to send out email notifications to our technicians when a ticket is assigned to them.

I am using a SendEmail component and i am trying to find an easy way (i.e. without having to edit the source in HTML mode) to send the URL to view the ticket.

I know there must be an easy answer, but i can't seem to find it!

Thanks!