Preheat your oven to 350°F (175°C) and grease two 9-inch round cake pans with butter and dust with flour.

In a large mixing bowl, sift together the all-purpose flour, granulated sugar, unsweetened cocoa powder, baking powder, baking soda, and kosher salt.

In a separate bowl, whisk together the room temperature eggs, whole milk, vegetable oil, warm water (or coffee), and pure vanilla extract until smooth.

Pour the wet ingredients into the dry mixture and gently fold with a spatula until no flour pockets remain.

Divide the batter evenly between the prepared cake pans and smooth the tops for an even bake.

Bake for 25-30 minutes and check for doneness with a toothpick.

Cool the cakes in the pans for about 10 minutes, then invert them onto a wire rack to cool completely.

For the ganache, heat the heavy cream over medium heat until it simmers, then pour it over the chopped dark chocolate and stir until smooth.

Once cooled, spread half of the ganache over one cake layer, place the second layer on top, and frost the entire cake with the remaining ganache.