10 tablespoons unsalted butter
1 cup Guinness stout
3/4 cup unsweetened cocoa
2 cups sugar
3/4 cup reduced-fat sour cream
2 large eggs
2 cups all-purpose flour
1 tablespoon vanilla extract
2 1/2 teaspoons baking soda
1 Pre-heat oven to 350 degrees.
2 Grease a 9-inch springform pan and line with parchment paper.
3 In a large saucepan, combine Guinness and butter.
4 Place over medium-low heat until butter melts, then remove from heat. Add cocoa and sugar, and whisk to blend.
5 In a small bowl, combine sour cream, eggs and vanilla; mix well.
6 Add to Guinness mixture. Add flour and baking soda, and whisk again until smooth.
7 Pour into buttered pan, and bake until risen and firm, 45 minutes to one hour. Place pan on a wire rack and cool completely in pan.