01 -
Turn oven on to 350°F. Coat two loaf pans with butter and flour or line with foil and spray with cooking spray.
02 -
Follow package instructions to make the cake batter. Split it evenly between both pans.
03 -
Whip cream cheese and sour cream until creamy. Stir in egg, sugar, and vanilla. Place dollops over the cake mix and run a knife through to create swirls.
04 -
Pop in oven for 30-40 minutes. It's done when you stick a toothpick in and it comes out clean. Let cool all the way.
05 -
Whip butter with cream cheese. Add powdered sugar, salt, and vanilla, mixing until fluffy. Spread on top of cooled cakes.