• Preheat oven to 325°F convection (with fan) or 350°F conventional (no fan)
• Spray pan with cooking spray and then flour it. Tap the flour around until every inch is covered. Tap out the extra flour onto a piece of parchment on the counter. You should be left with a perfectly floured pan. I have found that coating the pan with cocoa powder causes more detailed molds to stick and I’m not about that added stress.

Make the Cake:

• Whisk together flour, cocoa powder, salt and baking soda. Set aside.
• Melt the chocolate and then allow to cool. It should be warm but not hot.
• Whisk together the sour cream and water.
• In the bowl of a stand mixer fitted with the paddle attachment, beat butter and sugars just until a thick paste forms. Beat in the eggs one at a time, scraping down the sides of the bowl after every two eggs or so. Add the vanilla extract with the last egg.
• Add all the melted chocolate at one time and beat well to incorporate.
• Switch the mixer to low and then alternately add the flour and sour cream mixture. I don’t wait until all the flour has incorporated until I add the next batch. I just keep adding with two hands. Pro-style. I do stop the mixer to add the last of the sour cream mixture because I like to scrape it all out with a rubber spatula.
• Pour into prepared pan and smooth the top with the back of a spoon.
• Bake in preheated oven until a cake tester comes out with a few clinging crumbs. This will take about 60-85 minutes depending on your oven. Mine baked for 70 minutes. If you overbake it will be dry.
• Let her COOL 20 minutes and then loosen the edges with a paring knife and then turn it out onto a rack. Allow to cool completely.
• Dust with powdered sugar or make a simple glaze or a chocolate ganache like I did!

Make the chocolate ganache:

• Place chopped chocolate or chocolate chips in a medium bowl set on a folded tea-towel. Heat cream in a small saucepan just until it comes to a boil then pour over the chocolate.
• Allow the cream to sit on the chocolate undisturbed for 2 minutes. This melts the chocolate and will allow you to emulsify the ganache easily with less whisking. Less whisking means less of a chance for the ganache to break. I find a whisk is more efficient for emulsifying than stirring with a spoon or rubber spatula.
• Start whisking in one direction in the center of the chocolate until you see a smooth ganache beginning to form. Then gradually make your whisking strokes larger, pulling in more of the cream. Once a smooth ganache forms, stop whisking.
• Allow the ganache to cool slightly before pouring over the top of the cooled cake.