Chocolate Stout Cake (Justin and May's Wedding Cake)

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

Heat oven to 350°F. Grease and flour a 10- or 12-cup Bundt pan, or 2 8-inch round cake pans.

Bring 1 cup stout and 1 cup 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 3/4 teaspoon 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. Pour batter into prepared pan. Bake cake until tester inserted into center comes out clean, about 35 minutes. Transfer cake to rack; cool completely in the pan, then turn cake out onto rack.

From Barrington Brewery via Epicurious, and also from Smitten Kitchen