Preheat your oven to 350ºF (175ºC) and grease two 9-inch baking pans with butter or spray.

In a stand mixer, combine the flour, sugar, cocoa powder, baking soda, and salt on low speed for 1 minute.

Add eggs, buttermilk, melted butter, and vanilla to the dry mixture; mix on medium for 30 seconds, scrape, then mix for another 15 seconds until mostly smooth.

Fold in the hot coffee carefully until combined.

Divide the batter into the prepared pans and bake for 25-35 minutes, checking doneness with a toothpick.

Let the cakes cool in the pans for 15 minutes, then release onto wire racks to cool completely.