Tony-award winner Menzel, who provides the voice for Queen Elsa in film, appeared on American TV singing the track.
It's one of the brand new songs written by husband and wife team Robert Lopez and Kristen Anderson-Lopez that feature in the sequel to the 2013 movie, out in cinemas now.
You can watch Idina Menzel singing Show Yourself live below...
The full Frozen 2 soundtrack is available now on CD, download and streaming.
Frozen 2 is the follow up to Disney's 2013 hit animated musical that introduced us to royal sisters Elsa and Anna, and gave us the hit song Let It Go.
Idina Menzel and Kristen Bell reprise their roles as Queen Elsa and Princess Anna respectively for Frozen 2. Josh Gad returns as Olaf and Jonathan Groff is back as the voice of ice harvester Kristoff.
New cast members include Evan Rachel Wood and Alfred Molina as Queen Iduna and King Agnarr, the late parents of Elsa and Anna.
Revealing a synopsis for the movie, Disney teased: "Why was Elsa born with magical powers? The answer is calling her and threatening her kingdom. Together with Anna, Kristoff, Olaf and Sven, she'll set out on a dangerous but remarkable journey.
"In Frozen, Elsa feared her powers were too much for the world. In Frozen 2, she must hope they are enough."