01 - Preheat oven to 350°F. Grease and flour two 9-inch round cake pans, then line the bottoms with parchment paper.
02 - Whisk together flour, sugar, baking soda, salt, and cocoa powder in a large bowl.
03 - In a separate bowl, blend vegetable oil, buttermilk, eggs, red food coloring, vanilla extract, and vinegar until smooth.
04 - Gradually add the wet mixture into the dry ingredients, folding with a spatula until just combined and smooth without lumps.
05 - Evenly pour batter into 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. Remove from pans and cool completely on a wire rack.
08 - Beat cream cheese and butter in a large bowl until smooth and creamy.
09 - Gradually incorporate confectioners sugar, vanilla extract, and salt. Continue beating until light and fluffy.
10 - Place one cake layer on a serving plate. Spread with one-third of the frosting. Add second layer and cover top and sides with remaining frosting.
11 - Refrigerate for 30 minutes to firm frosting before slicing for clean edges.