Preheat oven to 350°F (175°C). Grease and lightly flour two 8 inch round cake pans, then line the bottoms with parchment paper.
Sift flour, cocoa powder, baking powder, and baking soda into a large bowl. Whisk in both sugars and salt.
In a separate bowl, whisk eggs, oil, sour cream, and vanilla until combined.
Pour the wet ingredients into the dry ingredients and mix until blended.
Gradually mix in the hot coffee until the batter is smooth and thin.
Divide between the pans and tap to release air bubbles. Bake 30 to 33 minutes, until a toothpick comes out clean.
Cool in the pans for 15 minutes, then invert onto a wire rack to cool completely.
Frost with chocolate fudge frosting once fully cool.