Stout Chocolate Cake with Ganache

For the cake:
1. Preheat oven to 350°F and butter 2 deep 9-inch round cake pans.
2. Bring stout and butter to a simmer in a heavy large saucepan over medium heat. Add cocoa powder and whisk until mixture is smooth. Remove from heat and cool slightly.
3. Whisk flour, sugar, baking soda, and salt in a large bowl to blend.
4. In another large bowl, using an electric mixer, beat eggs and sour cream to blend.
5. Add stout mixture to egg mixture and beat just to combine. Add flour mixture and stir briefly until combined.
6. Divide batter equally among pans. Bake 35-40 minutes, until toothpick comes out clean.
7. Transfer cakes to rack and cool completely before icing.

For the icing:
1. Bring cream to simmer in heavy medium saucepan. Remove from heat.
2. Add chopped chocolate and whisk until melted and smooth.
3. Refrigerate until icing is spreadable, stirring frequently, about 1-2 hours.
4. Place first cake layer on plate. Spread 1 cup icing over. Top with second cake layer. Spread remaining icing over top and sides of cake.