This cake is an intensely rich chocolate cake. It is sure to spark joy in every chocolate lover!
Preheat oven to 350Fº. Grease four 9" X 3" cake rounds. Add a circle of parchment paper to each pan; set aside.
In a medium bowl, combine the cocoa powder and boiling water; stir together; set aside.
In a medium bowl, whisk together the dry ingredients - flour, baking soda and salt; set aside.
In the bowl of an electric mixer, beat the sugar, oil, sour cream, eggs, and 1 tablespoon vanilla. Add the cooled cocoa mixture. Mix together.
Reduce to low speed, add the dry ingredients. Beat just until smooth.
Divide the mixture between pans. Bake for 30 to 35 minutes, or until a toothpick inserted in the center comes out clean.
Cool the layers in the pans on wire racks for 15 to 20 minutes. Invert them onto a wire rack; cool completely.