Swiss Meringue Buttercream
6 egg whites
2 cups white sugar
3 cups unsalted butter, at room temperature
1 tablespoon vanilla extract
1. Place the egg whites and sugar into a metal bowl and set over a pan filled with about 2 inches of simmering water. Stirring frequently, until the temperature of the egg whites reaches 140 degrees. I didn't have anything to measure the temperature with so I heated/stirred until the gritty texture was completely gone.
2. Transfer the heated egg whites and sugar to a large mixing bowl or stand mixer. Mix at high speed (or as high as you can go without egg flying out of the bowl) until they have reached their max volume, 5 to 10 minutes and are stiff and glossy.
3.Mix on medium or medium-high speed while throwing in small pieces of butter and mix in vanilla. The buttercream may look like it is breaking down, but keep on mixing and it will come back together.
After I added the butter I thought I had ruined the icing, it became oddly runny and liquidy, so I left the machine running and hoped that it would somehow work out. I came back a bit later and my icing looked horrible, like it had curdled or become dry curd cottage cheese, slight panic set in but I figured that I had already ruined it so I would just let the mixer keep going and maybe it would smooth out. It did, about 10 minutes later I came back and it started to look like this:
After some googling it looks like I’m not the only one this happens to, so if you make this be prepared, it will turn into liquid then chunky curds and then glorious buttery goodness, don’t panic! Since I didn’t have enough icing to make this cake look nice I dressed it up with skor bits on the side, crushed chocolate bars and drizzled melted chocolate on top. In the end I think it looked great and it tasted pretty good too. The skor bits and topping ended up being really sweet but the icing wasn’t so it seemed to balance out.