01 -
Preheat oven to 175°C. Grease and flour two 23x13 cm loaf pans or line with baking paper and spray with nonstick spray.
02 -
Prepare the red velvet cake batter according to package directions using the specified eggs, water, and oil. Divide evenly between prepared loaf pans.
03 -
In a stand mixer, beat cream cheese and sour cream until smooth. Add egg, granulated sugar, and vanilla extract, and continue mixing until mostly smooth. Some small lumps may remain.
04 -
Spoon the cheesecake mixture over the cake batter in both pans. Using a butter knife or the back of a wooden spoon, gently swirl the cheesecake filling through the batter without over-mixing.
05 -
Bake in the centre of the preheated oven for 30–40 minutes or until a skewer inserted into the centre comes out clean. Allow to cool completely in the pans.
06 -
With a hand mixer, beat butter and cream cheese until smooth and creamy. Incrementally add powdered sugar, then blend in salt and vanilla extract. Mix until fully combined.
07 -
Remove cooled cakes from pans and cover tops with the prepared cream cheese frosting. Refrigerate until serving.