1. Preheat oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
2. In a large bowl, whisk together flour, sugar, baking soda, salt, and cocoa powder.
3. In a medium bowl, whisk together buttermilk, oil, eggs, food coloring, vinegar, and vanilla.
4. Gradually add wet ingredients to dry ingredients, mixing until just combined.
5. Divide batter evenly between prepared pans. Bake for 30-35 minutes until a skewer comes out clean.
6. Cool cakes in pans for 10 minutes, then invert onto a wire rack to cool completely.
7. For frosting, beat cream cheese and butter until fluffy. Gradually add powdered sugar, beating until smooth.
8. Mix in vanilla bean paste and salt.
9. Frost cooled cakes with cream cheese frosting. Serve and enjoy.