Ingredients

339 grams unsalted butter, room temperature 
400 grams powdered sugar
1 tsp vanilla 
½ tsp salt
75 grams Dutch processed cocoa powder
2-3 tbsp warm coffee

Frosts 24 cupcakes, or a double layer cake 

Instructions

The temperature of the butter is very important for making a smooth buttercream. Room temperature butter will make an indent when you poke it with your finger. 

In the bowl of a stand mixer fitted with the whisk attachment, whisk the butter on high speed for 5 minutes, or until light in colour, smooth, and very fluffy. Scrape down the bowl very well halfway through and again at the end, mixing again to thoroughly fluff all of the butter. The butter should be all light in colour with no yellow streaks.

 While the butter is being whipped, sift the powdered sugar and cocoa powder into a bowl using a fine mesh sieve. 

Add the vanilla, salt, and 1 cup of the sifted cocoa and powdered sugar to the butter. Drape a dish towel over the bowl to prevent the powdered sugar from flying out of the bowl. Mix on high speed for 1 minute.

Scrape down the bowl, then add another cup of the powdered sugar/cocoa. Repeat the process until all of the dry ingredients have been thoroughly incorporated and the bowl scraped.

Add the warm coffee to the bowl 1 tbsp at a time, mixing on high speed for 1 minute after each inclusion.

After 2 tbsp of coffee have been added and incorporated, check the consistency of the frosting. If it is too thick and creates jagged edges when you lift your paddle out, add in the rest of the coffee, looking for the perfect consistency to pipe from your piping bag. Check to make sure all of the butter is smoothed out by smearing a small portion over a piece of parchment paper. Even small pieces of hard butter will clog many piping tips, so take the time to mix the frosting well before you attempt to put it in a piping bag.

Once finished, use the frosting immediately. If using at a later date, refrigerate and then slowly bring the frosting to room temperature again before using.