Mariah Carey stopped by Late Night With Jimmy Fallon where she, Jimmy, The Roots and some youngsters performed the greatest Christmas song of all time, "All I Want For Christmas," using only music room instruments. Andd it was the most amazing rendition of this holiday classic ever.

So watch Jimmy on drums and woodblock, The Roots with recorders and xylophones and some adorable kids kill this holiday favorite.

And for anyone who should ever dare to question that legend Ms. Carey, let it be known -- she sounds flawless. And looks flawless too.

God we love the holiday season.

Watch it above.

Mariah Carey Lights Up Rockefeller Center Christmas Tree