Lady Gaga has a Christmas gift for you — and it’s delicious. The pop star sang her fan-favorite holiday song “Christmas Tree” for the first time in 16 years, giving us a dirty little dose of Christmas spirit. Now, it was just for Carpool Karaoke, but we’ll take what we can get! Gaga popped into the SUV for the surprise A Carpool Karaoke Christmas special (on Apple TV), joining guest driver Zane Lowe, filling in for the usual James Corden. Lowe feigned surprise and horror at the raunchy Christmas song’s lyrics...