Preheat the oven to 180°C. Grease a 9-inch round cake pan and line it with parchment paper.
In a large bowl, mix 200 grams of all-purpose flour, 50 grams of cocoa powder, 1 teaspoon of baking soda, and 1/2 teaspoon of salt. Set aside.
In another bowl, combine 200 grams of sugar, 240 ml of milk, 120 ml of vegetable oil, 1 tablespoon of white vinegar, and 1 teaspoon of vanilla extract. Mix well.
Gradually add the wet ingredients to the dry ingredients, mixing until a smooth batter is formed.
Pour the batter into the prepared cake pan and tap it gently to remove any air bubbles.
Bake the cake for 30-35 minutes, or until 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 it to a wire rack to cool completely.
Once the cake is completely cooled, spread a layer of chocolate ganache or frosting of your choice on top and serve.