Preheat your oven to 180°C (350°F). Grease and lightly flour a 23cm (9-inch) round cake pan.
Sift together the flour, cocoa powder, baking soda, and salt into a large mixing bowl to aerate the dry ingredients.
In a separate bowl, beat the sugar and vegetable oil with an electric mixer until the mixture is smooth and slightly fluffy, releasing a sweet aroma.
Add the eggs one at a time, beating well after each addition until the batter is glossy and smooth.
Pour in the buttermilk and add the white vinegar, mixing until well combined and the batter appears slightly thinner.
Gradually add the sifted dry ingredients into the wet mixture, alternating with the red food coloring, starting and ending with the dry ingredients. Mix until just combined and the batter is glossy and smooth.
Pour the batter into the prepared cake pan, smoothing the top with a spatula. Tap the pan gently on the counter to remove air bubbles.
Bake in the preheated oven for about 30 minutes, or until the edges pull slightly away from the pan and a toothpick inserted in the center comes out clean.
Remove the cake from the oven and let it cool in the pan for 10 minutes, then transfer to a cooling rack to cool completely.
Once cooled, frost and decorate as desired, then slice to reveal the bright, tender crumb with a deep, rich color and a slight cocoa aroma.
