Miley Cyrus has been having a busy couple of weeks. The 19-year-old singer/actress got engaged (before us -- we're still kind of bitter about it), is supposedly in the process of having her tattoos removed, and is now featured on a track called 'Morning Sun' by Rock Mafia.

But if the song looks and sounds familiar to you, that's because a demo was released a whopping two years ago. We know -- they've clearly been sitting on their butts those past two years. Video also surfaced featuring the former 'Hannah Montana' star recording the song in the studio, but alas, the official version is finally here!

Ms. Miley performs back-up vocals and can be heard repeating the lines, "Boo, I do / I wanna be with you / ’Til the morning sun" -- some Allen Ginsberg stuff right there. The song is fun, it's poppy, and we're a sucker for a good Miley Cyrus jam so whatevs. But we'll still be rocking 'Party in the USA' until we die.

Listen to Rock Mafia, 'Morning Sun' Feat. Miley Cyrus