01 - Preheat your oven to 350°F. Grease and line two 9-inch round cake pans with parchment paper.
02 - In a large bowl, whisk together flour, sugar, baking soda, salt, and cocoa powder until well blended.
03 - In a separate bowl, combine oil, buttermilk, eggs, food coloring, vanilla, and vinegar. Mix thoroughly until uniform.
04 - Gradually add the wet ingredients to the dry ingredients, mixing until just combined. Avoid overmixing to prevent tough texture.
05 - Divide the batter evenly between the prepared pans, smoothing the tops with a spatula.
06 - Bake for 28 to 32 minutes, or until a toothpick inserted in the center comes out clean.
07 - Cool the cakes in the pans for 10 minutes, then turn out onto a wire rack to cool completely before frosting.
08 - In a large bowl, beat the cream cheese and butter until smooth and creamy, about 2 to 3 minutes.
09 - Gradually add powdered sugar, vanilla, and salt. Beat until fluffy and well combined, scraping the bowl as needed.
10 - Place one completely cooled layer on a serving plate and spread with an even layer of frosting. Top with the second layer.
11 - Frost the top and sides of the cake. Decorate as desired and chill for at least 30 minutes before slicing for clean cuts.