Entire clear text emails. Everyone SHOULD be using TLS wrapped email protocols. That doesn't mean they are, but gmail is https all the way and many providers now require TLS connections to the mail servers.
Still, one time use password reset links with explicit instructions and set expectations to reset the password immediately is the way to go if you're emailing anything IMO.
Still, one time use password reset links with explicit instructions and set expectations to reset the password immediately is the way to go if you're emailing anything IMO.