Start by heating your oven to 350°F (175°C). Prepare two 9-inch round cake pans by greasing them well, then lining the bottoms with parchment paper so the cakes release easily later.
In a large mixing bowl, combine the flour, sugar, baking powder, baking soda, salt, and cocoa powder. Whisk everything together until the mixture looks uniform and there are no streaks of cocoa.
Add the vegetable oil, vanilla extract, eggs, and buttermilk to the dry ingredients. Mix until the batter is smooth and fully combined; making sure nothing is stuck at the bottom of the bowl.
While mixing, slowly pour in the hot water. Continue stirring until the batter becomes thin and smooth, with no lumps remaining.
Pour the batter evenly into the prepared cake pans and place them in the oven. Bake for about 30 to 35 minutes, checking for doneness by inserting a toothpick into the center of the cakes. If it comes out clean, they’re ready. Let the cakes sit in the pans for about 10 minutes, then carefully turn them out onto a cooling rack and allow them to cool completely.
To prepare the frosting, beat the butter until it is soft and creamy. Add the cocoa powder, powdered sugar, salt, almond extract, vanilla extract, and buttermilk. Beat until the frosting is smooth and fluffy, adjusting the powdered sugar if you need a thicker consistency.
Once the cakes are completely cool, spread frosting over the top of one cake layer. Place the second layer on top, then frost the top and sides evenly until the cake is fully covered and smooth.