1. Preheat Oven and Prep Pans:2. Preheat oven to 350°F (175°C). Grease and flour two 9-inch round cake pans (or one 9×13 inch pan). For dark cakes, dusting with cocoa powder instead of flour is recommended.3. 4. Whisk Dry Ingredients:5. In a large bowl, whisk together the all-purpose flour, granulated sugar, dark cocoa powder, baking soda, and salt.6. 7. Mix Wet Ingredients:8. In a separate medium bowl, whisk together the buttermilk, vegetable oil, large eggs, and vanilla extract.9. 10. Combine Batter:11. Pour the wet ingredients into the dry ingredients and whisk until just combined. The batter will be thick.12. 13. Add Hot Water:14. Slowly pour the hot water into the batter, whisking gently until the batter is smooth and thin. This step blooms the cocoa and adds moisture.15. 16. Bake the Cake:17. Pour the batter evenly into the prepared pans. Bake for 30-35 minutes for 9-inch rounds (or 35-40 minutes for a 9×13 pan). A toothpick inserted into the center should come out clean.18. 19. Cool Completely:20. Let the cakes cool in their pans for 15 minutes before inverting onto a wire rack to cool completely.21. 22. Make the Frosting:23. In a large bowl, beat the room-temperature cream cheese and butter with an electric mixer on medium-high speed until smooth.24. Reduce speed to low. Gradually add 3 cups of sifted powdered sugar, mixing until combined. Add the vanilla and salt.25. Beat on medium-high for 2 minutes until fluffy. Add more powdered sugar if a stiffer frosting is desired.26. 27. Frost the Cake:28. Once the cake layers are completely cool, frost the cake. Store the frosted cake in the refrigerator.