Preheat the oven to 350 degrees F. Grease and lightly flour a bundt pan or two 9" loaf pans. Set aside.

In a small bowl, whisk together the cocoa powder and sugar. Set aside.

In another small bowl, whisk together the flour and baking soda. Set aside.

Using a large saucepan, combine the Guinness and butter. Over low heat, stir the mixture until the butter melts and is blended with the Guinness. Stir in the sugar/cocoa mixture and blend until smooth. Remove from the heat.

Using a medium bowl, beat toggery the sour cream eggs, and vanilla extract. Then slowly stir this mixture into the chocolate mixture in the cooling saucepan. Then slowly stir in the flour/baking soda mixture. Stir until the batter is well mixed.

Carefully pour the batter into the greased bundt pan or the two loaf pans.

Bake for 45 to 55 minutes or until an inserted toothpick pulls out clean.

Cool the cake/breads completely before removing and placing on a serving plate.

In a medium saucepan, melt together the dark chocolate and heavy cream over a medium heat, stirring continuously. When the mixture is smooth and glossy, remove from heat and gently stir in the vanilla extract, salt, and Irish cream liquor (if you decide to use it).

Place the ganache in the refrigerator for about 8 minutes to thicken slightly. Then pour it over the cakes or breads. Serve with a side of whipped cream.