Gather all of the ingredients you need and preheat your oven to 350F. You’ll also need to grease and line two baking pans with parchment paper.

Grab a bowl and add the following ingredients: all-purpose flour, baking powder, baking soda, cocoa powder, and salt. You can pass the mixture of dry ingredients through a strainer to incorporate them better, then add the granulated sugar. Mix well using a paddle attachment and leave to one side.

In a separate bowl, add the vegetable oil, eggs, buttermilk (or alternative such as sour cream), and vanilla extract. Mix well.

Carefully add the bowl of wet ingredients, to the bowl of dry ingredients. Once completely mixed, pour in the hot water and mix on a low speed. Your batter should be thin at this point.

Distribute the batter evenly into your two pans and place them in the center of your preheated oven for around 35-40 minutes. Once your cakes are baked, a toothpick into the center should come out clean.

Leave your cakes to cool for 10 minutes and then remove them from the pans and transfer them to a wire rack. Cool completely.

Add your chocolate to a microwave-safe bowl and melt in 15-second intervals in a microwave, until completely melted. You can also choose the double boiler method if preferred.

In a bowl, add the butter and the confectioners’ sugar. Mix until the sugar is incorporated. Using a hand mixer, mix until pale in color. After a few minutes, it should be fluffy.

Gradually add your cocoa powder, melted chocolate, salt, and sour cream. Mix until you have a thick and smooth frosting.

Once your cake is completely cooled, add frosting in between the two layers and frost the top and sides of the entire cake. Decorate as desired. Slice, serve, and enjoy!