Step #4 In a large bowl sift together both sugars, cocoa powder, flour, baking soda, salt & cinnamon; set aside.
Step #5 In another bowl mix/whisk together the melted butter, buttermilk, water, oil, eggs & vanilla; add to the dry ingredients; mix well to mix until you have a smooth batter (I use a large whisk for mixing).
Step #6 Add in chocolate chips & nuts (if using).
Step #7 Pour into prepared baking dish.
Step #8 Bake for about 25-30 mins or until cake tests done.
Step #9 Cool completely before frosting.
Step #10 **NOTE** if using nuts reduce amount of chocolate chips to 1/2 c.