Originally Posted by ashivley
There are a bunch of recipes if you search for guinness buttercream, here is one that i found.
Guinness Buttercream Frosting
2 Cup(s) Unsalted Butter (room temperature)
5 Cup(s) Sifted Powder Sugar
1/2 Cup Milk
1 Whole Scraped Vanilla Bean
1 Tablespoon Vanilla Extract
2 Cup(s) Guinness Extra Stout
In a sauce pan, simmer Guinness on low heat for 10-15 min, until it stout becomes reduced and thicker in consistency. Similar to a syrup. *Tip: keep your eye on the store, so stout does not over cook. Let cool.
In a stand alone mixer, cream your butter for 1 minute
Slowly add the powder sugar in thirds, alternating with a little milk each time till mixture is creamy.
Add scraped vanilla bean and vanilla extract.
Slowly add reduced Guinness a little at a time. Taste test to desired flavor. You may not use all the Guinness reduction.
It is just me or the amount of liquid sees like a LOT!?! Adding 2 1/2 plus 1 Tbsp of liquid to 1 batch of BC is too much!
What I do to my Beer BC is just replace the liquid the recipe calls for with reduced stout. Same amounts. I've also used Sam Adams, it is not as dark but just as good, little lighter in beer flavor.
I also use it with chocolate cake and brush my cake with some more reduced beer.