2 cups granulated sugar
1 cup light brown sugar, packed
2 and 3/4 cups plain flour
1 and 1/2 cups unsweetened cocoa powder, sifted
3 teaspoons baking soda
1 and 1/2 teaspoons baking powder
1 and 1/4 teaspoons salt
3 large eggs + 2 large egg yolks
1 and 1/2 cups full-fat sour cream
1/3 cup whole milk
3/4 cup canola oil
2 tablespoons vanilla extract
1 and 1/2 cups hot water
Preheat oven to 350°(F).
Line two 9-inch round tins Spray each pan generously.
In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl using a handheld electric mixer, combine both sugars, flour, cocoa powder, baking soda, baking powder and salt.
Mix on low until dry ingredients are thoroughly combined.
Use your hands to break up any large clumps, if needed.
In a separate bowl combine the eggs, egg yolks, sour cream, milk, oil and vanilla extract;
mix until completely combined. Pour mixture into the dry ingredients and beat on low until just incorporated.
Pour in hot water and continue mixing until completely combined; about 1 minute.
The batter will be quite thin.
Divide batter evenly among prepared pans. Bake in preheated oven for 30 minutes, or until a wooden toothpick or cake tester inserted in the centre of a cake comes out clean or with just a few moist crumbs attached. Cool cakes for 10 minutes in the pan before removing from pans and transferring to a cooling rack; cool cakes completely before frosting.