Chocolate Guinness Cupcakes

Pre-heat oven to 350 degrees.

Grease a 9-inch springform pan and line with parchment paper.

In a large saucepan, combine Guinness and butter.

Place over medium-low heat until butter melts, then remove from heat. Add cocoa and sugar, and whisk to blend.

In a small bowl, combine sour cream, eggs and vanilla; mix well.

Add to Guinness mixture. Add flour and baking soda, and whisk again until smooth.

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.