Method:

1. Preheat oven to 325 degrees
2. In an electric mixer, beat eggs and sour cream
3. In another bowl, combine flour, sugar, baking soda, and salt.
4. Combine coffee stout and butter in a small saucepan and heat until butter melts. Remove from heat and whisk in cocoa powder. 
5. While mixer is running, slowly pour in hot cocoa/butter mixture. Mix until fully incorporated. 
6. Slowly add dry goods to wet and beat until incorporated. Fill lined cupcake tins 2/3 with batter.
7. Bake for 10 minutes and let cool on a cooling rack. 

1. Simmer cream over medium heat until just bubbling. Take care not to boil over.
2. Meanwhile, chop the milk chocolate into chunks and transfer into a bowl.  
3. When cream is heated pour over room temperature chocolate.
4. Let chocolate and cream mixture sit for a minute or so, and then whisk. When smooth, add the butter. Ganache should be glossy. 
5. While whisking, stream in port until incorporated.
6. Transfer to a squeeze bottle. 

1. In an electric mixer, beat butter with paddle until fluffy.
2. On low speed, add the powdered sugar. 
3. Slowly stream in espresso and beat until smooth. 
4. Stir in espresso powder and transfer to a piping bag. 

1. When cupcakes are cool, use a small pastry tip to core out the center.
2. Fill the cupcakes with the port ganache, using a squeeze bottle. 
3. Frost the cupcakes to your liking.