Swiss Meringue Buttercream

I've been wanting to try this icing for what seems like ages now, and I finally had the opportunity to do so this past weekend! I made my mom a mothers day cake, and one thing that I know she really hates is icing that is "too sweet". I've heard so many good things about Swiss Meringue Buttercream, that I was really anxious to try it for her.

This icing was so great!!! My mom absolutely loved it, she said it tasted just like the buttercream under the fondant on my wedding cake, which she really loved. It's definitely not sickeningly sweet which is very pleasant. I actually had a lot of fun making it, too. Granted it was a bit time consuming but with my Kitchen Aid stand mixer I didn't have any issues at all. It's really funny to watch it transform, too. When I was whisking the butter into the egg white mixture I was sure I did something wrong. It just looked soupy and not at all like buttercream. Then on one of my last few pieces of butter, I looked down and it had transformed in an instant! I was like a kid who just finished a science experiment! So the moral of the story is, if you make this, don't give up on it! Even if it looks wrong throughout the process, it's probably not if you followed the recipe. For me, it didn't look like real buttercream until the VERY end.

***Please note: I halved this recipe for one 9" 2 - layer cake. I filled the middle with the buttercream as well, which worked perfectly. I didn't have too much or too little, halving it was perfect for the size cake I made.

Ingredients
Source: Martha Stewart

2 1/2 cups sugar
10 large egg whites
4 cups (8 sticks or 2 pounds) unsalted butter, cut into pieces (I used room temperature)
2 teaspoons pure vanilla extract
Directions

1. Place sugar and egg whites in the heat-proof bowl of an electric mixer. Set bowl over a pan of gently simmering water, and whisk until sugar has dissolved and egg whites are hot to the touch, about 3 minutes. Test by rubbing the mixture between your fingers; it should feel completely smooth.
2. Transfer bowl to mixer stand. Using the whisk attachment, beat on high speed until mixture has cooled completely and formed stiff and glossy peaks, about 10 minutes.
3. Add the butter, one piece at a time, and beat until incorporated after each addition. Don't worry if the buttercream appears curdled after all the butter has been added; it will become smooth again with continued beating. Add vanilla, and beat just until combined.
4. Switch to the paddle attachment, and beat on the lowest speed to eliminate any air pockets, about 5 minutes. If using buttercream within several hours, cover bowl with plastic wrap, and set aside at room temperature in a cool environment. Or transfer to an airtight container, and store in the refrigerator, up to 3 days. Before using, bring buttercream to room temperature, and beat on the lowest speed with the paddle attachment until smooth, about 5 minutes.