The recording sessions were a family affair with Lee's dad on ukulele, banjo and dobro and her sisters adding vocals, guitar, bass and harmonica.
The singer told Rolling Stone: "We've been saying, even if we're the only ones who ever heard it ... it was worth it because it means so much to us as a family and we love it.
"I'm always looking for ways that I can expand myself creatively and this was a surprise. This kind of came out of a very random place and a very pure place. It was just for ourselves and it turned into something really beautiful."
Dream Too Much will be available as an Amazon Music exclusive on September 30.
And in case you've forgotten what Amy Lee used to sound like in Evanescence, here's a reminder: