Step 1

Preheat the oven to 350°F. Prepare 3 8-inch round baking pans, line the bottom with parchment paper and grease the sides. Prepare your bake even stripes if desired.

Step 2

In a large mixing bowl, combine the sugar, vegetable oil, eggs and vanilla extract. Beat on medium speed until the eggs and oil are well incorporated and the batter is lighter in color.

Step 3

Next mix in the sour cream and beat until well combined.

Step 4

In a separate bowl, sift together the dry ingredients. Then add half the dry ingredients followed by half of the Guinness and mix just until the flour starts to incorporate.

Step 5

Finally, add the remaining dry ingredients, mixing on low speed while pouring in the remaining Guinness and beating until all of the ingredients are well combined.

Step 6

Use a spatula to scrape down the sides of the bowl and stir the batter from the bottom to the top to ensure it’s well mixed.

Step 7

Divide the batter evenly between the three pans, about 1 2/3 cups of batter per pan. Bake at 350°F for 20-24 minutes. Rotate your pans in the oven halfway through baking.

Step 8

Test the cake for doneness by inserting a toothpick into the center of the cake. If the toothpick comes out clean, your cake is done. Remove from the oven and allow to cool completely.

Step 9

Cut the butter into pieces, about 1 tablespoon in size. Using the paddle attachment, whip butter for 3-4 minutes, scraping down the bowl occasionally. Beat until butter looks light in color. Next, beat the cocoa powder into the butter until well mixed.

Step 10

Alternate adding 2-3 cups of powdered sugar at a time with the liquid ingredients: vanilla extract, heavy cream and stout. Add pinch of salt as needed. Ensure all the powdered sugar is well combined and beat for 2-3 minutes before adding additional powdered sugar.

Step 11

Once all ingredients have been added, whip for 3-4 minutes until the frosting is light and airy. If the frosting is too thick, add additional heavy whipping cream 1 tablespoon at a time.

Step 12

Level off your cakes by removing any domes. Place a dollop of frosting on your cake board and place the bottom layer of cake over that.

Step 13

Pipe the first layer of frosting, pipe in circles working outside edge to the middle. Spread evenly with an offset spatula. Add the second layer of cake and add the remaining frosting. Place the third layer of cake on top.

Step 14

Proceed to add your crumb coat by adding a cup of frosting to the top of the cake and gently spread out to the edges and down the sides. Using an offset spatula or icing smoother, the wipe away excess frosting, leaving you just enough to coat the outside of the cake. Do not mix your crumb coating frosting back into your icing if it has cake debris in it. Refrigerate the cake for 15-20 minutes to allow the crumb coat the harden.

Step 15

First, add about ½ cup of frosting to the top of the cake and create a nice, smooth top. Use your Viva paper towel and fondant smoother to create a flat even surface.

Step 16

Put remaining frosting in a 18-inch piping bag fitted with a Wilton #789 icing tip. Pipe the outside edge of the cake working from the bottom to the top. Use your icing smoother or large offset spatula to smooth edges and remove excess frosting.

Step 17

To pipe the rosettes on top, use a large piping bag fitted with a large open star tip, fill the piping bag with the remaining frosting and pipe the boarder of the cake. You can add a decorative boarder around the bottom edge. I used a tip #21 star tip.