01 - Preheat oven to 350°F. Grease and flour two 9-inch round cake pans, then line bottoms with parchment paper.
02 - Whisk together flour, sugar, baking soda, salt, and cocoa powder in a large bowl.
03 - In a separate bowl, combine vegetable oil, buttermilk, eggs, red food coloring, vanilla extract, and vinegar; mix until smooth.
04 - Gradually add wet ingredients to dry, folding gently with a spatula until just combined and no lumps remain.
05 - Distribute batter evenly between prepared pans.
06 - Bake for 28 to 32 minutes, or until a toothpick inserted in the center comes out clean.
07 - Allow cakes to cool in pans for 10 minutes, then invert onto wire racks to cool completely.
08 - Beat cream cheese and butter together until smooth and creamy.
09 - Gradually beat in confectioners sugar, vanilla extract, and salt until light and fluffy.
10 - Place one cake layer on a serving plate; spread with one-third of the frosting. Top with second layer, then frost top and sides with remaining frosting.
11 - Refrigerate the assembled cake for 30 minutes before slicing to ensure clean edges.