What's Baking: Swiss Meringue Buttercream

It's that time again! There was another What's Baking? challenge. This one was "try something new for the new year." When I read that, I immediately thought of egg whites. I've never made a meringue before. But then, I remembered that I don't really like meringue pies or meringue cookies much. And a better idea struck. On my message board, everyone RAVES about a specific kind of frosting. One that I've been meaning to try for a while and haven't gotten around to. One that works with egg whites. Specifically, Swiss meringue buttercream.


Conveniently, it was my friend's birthday, so I wanted to make cupcakes for him. Because, you know, I never bake for birthdays. Ever. /sarcasm. I wasn't sure as to his exact flavor preferences, but his wife assured me he liked everything. That's easy enough. I settled on vanilla bean cupcakes filled with homemade lemon curd and frosted with vanilla Swiss meringue buttercream (of course).

These turned out really well! They were a hit with everyone who tried them. And the Swiss meringue buttercream was actually fairly forgiving. I was making a small batch, and I don't think my thermometer was immersed quite enough to get an accurate reading, so I'm pretty sure I cooked my egg whites pretty well past 160 degrees. In spite of this (and in spite of smelling disturbingly like scrambled eggs), the frosting came together fine and tasted alright. Now, personally, I don't like the taste of butter (*gasp*). And the difference between this frosting and the normal American buttercream that I usually make is that the Swiss meringue buttercream has a lot less sugar and a lot more butter. So, it wasn't my personal favorite in terms of flavor. I also found it very difficult to pipe. I never quite got to stiff peaks like the recipe calls for, as my egg white/sugar mixture was more like a marshmallow fluff consistency after cooking and whipping than light and airy peaks, so this is probably my own fault, and probably wouldn't have happened had I not overcooked the egg whites. I think the Swiss meringue buttercream is also a LOT more time-consuming than an American buttercream. So, while I'm not a convert, it was good to try something new!


Vanilla Bean Cupcakes (from Annie's Eats)

• 2 sticks of butter, softened
• 2 c. granulated sugar
• 1 vanilla bean
• 5 eggs
  
• 3 c. flour (the original recipe calls for cake flour, but I used AP)
  
• 1 Tbl. baking powder
• 1/2 tsp. salt
• 1 1/4 c. buttermilk
• 1 Tbl. vanilla extract

Cream together the butter and sugar. Split open the vanilla bean, scrape out all the seeds, and add the seeds to the butter and sugar. Then, beat in the eggs, one at a time. Sift together the dry ingredients, and add them to the butter/sugar mixture in two additions, alternating with the buttermilk and vanilla extract. Mix just until combined.

Using an ice cream scoop, scoop the batter into well-greased muffin tins. This will make about 27 or 28 cupcakes. Bake at 350 degrees F for 18-22 minutes, or until a toothpick inserted into the center comes out clean.

Orange Curd (from Food and Wine)

• 3 eggs
• 2 egg yolks
• 1/2 c. sugar
• 1/4 c. orange juice
• 2 Tbl. lemon juice
• 2 tsp. orange zest
• 2 tsp. lemon zest
• 1 stick of butter, softened, cut into small pieces

Whisk together eggs, egg yolks, and sugar in a small-to-medium saucepan. Whisk in the orange juice, lemon juice, and zests. Add butter. Cook over medium-low heat, whisking constantly, until the mixture thickens. Strain it through a fine-meshed sieve to remove any lumps and the zest. Cover with plastic wrap, pressing the plastic directly against the surface of the curd to prevent a skin from forming. Refrigerate overnight or up to one week.

Swiss Meringue Buttercream (from Annie's Eats)

• 5 egg whites
• 1 c. plus 2 Tbl. granulated sugar
• Pinch of salt
• 4 sticks of butter, softened, cut into small pieces
  
• 2 tsp. vanilla extract

Mix together the egg whites, sugar, and salt in a heatproof bowl (I used my mixer's metal bowl). Set it over a pot of simmering water, and cook, whisking constantly, until mixture reaches 160 degrees F. Transfer the mixture to the bowl of a stand mixer (if needed), and whip on medium-high speed until stiff peaks form and the mixture has cooled to room temperature. Now, add the butter, about 2 Tbl. at a time, making sure to completely beat in each piece before adding the next. Note: the original recipe says that the recipe may look soupy or curdled at this point--mine didn't, but mine was also bordering on scrambled eggs. So, if that happens to you, don't panic. It means you're doing it right. Just keep mixing, and it will eventually come together. Once it does, mix in the vanilla extract. The frosting can be refrigerated for a couple days--just whip it up a little before you use it.

To assemble:

Take the cooled cupcakes, and cut a plug approximately 1 inch in diameter out of the center of each cupcake. The plug should NOT go all the way through the cupcake. Dispose of these plugs in any manner you like (personally, I ate them). Fill each cupcake with orange curd. Then, frost each cupcake with the Swiss meringue buttercream, trying not to disturb the orange curd. Devour.