Watch If/Then's Idina Menzel Sing Joni Mitchell & Talk Wicked Witches Going Commando

Last time Frozen star Idina Menzel stopped by The Tonight Show she "Let It Go" and went viral; on December 15 the Tony winner was granting all our Holiday Wishes, soulfully singing Joni Mitchell's "River" from her latest album. The If/Then headliner also revealed one of her favorite holiday traditions, which features a reminder of her Tony-winning turn in Wicked that involves wearing no underwear!?! Check out the videos below and then Menzel in person at the Richard Rodgers Theatre!