Cake
8 oz (2 sticks) sweet unsalted butter, cut into bits
1 cup Guinness stout
1/2 cup natural cocoa powder
1/4 cup black cocoa powder
2 cups granulated sugar
3/4 cup sour cream
2 large eggs
1 tbsp vanilla extract
2 cups all-purpose flour
2½ tsp baking soda
butter to grease baking pan or rings

Sabayon
6 large egg yolks
1/4 cup granulated sugar
1/3 cup water
1/3 cup Irish cream liqueur
1 oz bittersweet chocolate + 2 oz milk chocolate, chopped & melted
3/4 cup heavy whipping cream, whipped to soft peaks
pinch of kosher salt

Special Equipment
twelve 3" diameter pastry rings, cupcake tins or 9" x 3" round baking pan
parchment paper
foil
baking sheet