Deleting a host named site collection... for real

A simple problem: you have to delete a host named site collection in order to recreate it.
When you try to recreate it, you get an error: SharePoint says the site collection already exists... if you restart the machine you'll be able to recreate it.
What if you cannot restart the machine whenever you want (read production environment).

$variable = Get-SPSite "http://already.deleted.site"
$variable

You'll get an output like this

Now recreate the site collection without problems ;)