Nutmeg Cinnamon Swiss Meringue Buttercream

Let me just tell you a story about my experiences with Swiss Meringue Buttercream (otherwise known as SMC).  When I first started really concentrating on baking I knew I needed to find a new frosting for my cakes and cupcakes.  I am not a big fan of the really sweet American Buttercream (lots of powdered sugar).  After doing some research on the internet I found that SMB was my best option.  I had never really had a SMB before and so I had no idea what it should look or taste like.  My first batch actually came out perfectly but I didn't know that at the time.  I was expecting it to a lot like American Buttercream, really sweet, not what it actually was, buttery and silky.  I LOVED it!  I could eat it by the spoonfuls.  But, because I was thinking it would be more like the American Buttercream I was confused as to why it didn't have powdered sugar in it, so I added a little bit, and then a little bit more, and then some more.  I have probably crossed some SMB honor code by adding powdered sugar to mine.  The thing was...I loved it even more after adding the powdered sugar, so now, all my SMB has powdered sugar in it.

Nutmeg Cinnamon Swiss Meringue Buttercream
adapted from Martha Stewart's Swiss Meringue Buttercream

Ingredients
5 large egg whites
1 cup plus 2 tablespoons sugar
4 sticks butter, cut into pieces
1 1/2 teaspoons vanilla
1/2 teaspoon ground nutmeg
1 teaspoon ground cinnamon
1/3 cup powdered sugar

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. Add nutmeg, cinnamon and powdered sugar at this point and mix on medium speed until incorporated.
5. 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.