Preheat your oven to 350°F (175°C).
Grease and flour two 9-inch round cake pans.
In a bowl, combine flour, baking soda, salt, and cocoa powder.
In another bowl, mix oil, sugar, buttermilk, eggs, food coloring, vanilla, and vinegar until smooth.
Gradually add dry ingredients to the wet mixture, stirring until just combined.
Divide the batter evenly between the prepared pans.
Bake for 30-35 minutes or until a toothpick comes out clean.
Let the cakes cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.
Frost with cream cheese frosting once cooled.
Decorate as desired and serve.