chocolate stout cake

INGREDIENTS

• 1 cup stout (such as Guinness)
• 1 cup (2 sticks) unsalted butter
• 3/4 cup 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
• 6 ounces good semisweet chocolate chips
• 6 tablespoons heavy cream
• 3/4 teaspoon instant coffee granules