Avril Lavigne & Robert Downey Jr.: Guests on 'Leno'!

Avril Lavigne rocks a little black dress while performing on The Tonight Show with Jay Leno on Friday (April 26) in Burbank, Calif.

“We are performing on @jayleno tonight! 11:35/10:35c… Here’s to Never Growing Up!” the 28-year-old singer tweeted with a pic. Check out the cute pic below!

Avril was joined on the show by Robert Downey Jr, who promoted his new flick Iron Man 3, hitting theaters on Friday, May 3!

The day before, Robert‘s co-star Gwyneth Paltrow also appeared on the show to chat about the highly-anticipated film.