Chocolate Stout Cake

Alright (sorry about my foodie friends absence), I made this last year for St. Patrick's Day weekend and it is pretty amazing. It was requested again this year by my in-laws. Last year I was a little wimpy and just made a sheet cake, but this year I went big and made my first three layer cake. I know it is a little industrious but well worth it! It to is from Epicurous (after you look at the ingredients you'll know why I only make it once a year).

Cake
2 cups stout (such as Guinness)
2 cups (4 sticks) unsalted butter
1 1/2 cups unsweetened cocoa powder (preferably Dutch-process)
4 cups all purpose flour
4 cups sugar
1 tablespoon baking soda
1 1/2 teaspoons salt
4 large eggs
1 1/3 cups sour cream

Icing
2 cups whipping cream
1 pound bittersweet (not unsweetened) or semisweet chocolate, chopped

For cake:
Preheat oven to 350°F. Butter three 8-inch round cake pans with 2-inch-high sides. Line with parchment paper. Butter paper. Bring 2 cups stout and 2 cups butter to simmer in heavy large saucepan over medium heat. Add cocoa powder and whisk until mixture is smooth. Cool slightly.
Whisk flour, sugar, baking soda, and 1 1/2 teaspoons salt in large bowl to blend. Using electric mixer, beat eggs and sour cream in another large bowl to blend. Add stout-chocolate mixture to egg mixture and beat just to combine. Add flour mixture and beat briefly on slow speed. Using rubber spatula, fold batter until completely combined. Divide batter equally among prepared pans. Bake cakes until tester inserted into center of cakes comes out clean, about 35 minutes. Transfer cakes to rack; cool 10 minutes. Turn cakes out onto rack and cool completely.

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