*** This post was originally written on The Good Egg blog in August, 2008.
I remember the exact time I made my first true buttercream. It was the night before my sister’s wedding shower and I wanted to make the cake to end all cakes. I decided to do half the recipe of Anna Olson’s wedding cake from the “Inn On the Twenty” cookbook. As I was making the buttercream, I was completely amazed at the process and the taste. It was a real revelation that I could create this silky, other-worldly icing, and you can bet that I tasted my fair share of it along the way! Giddy would be a great way to describe me that night as I danced around the kitchen, drunk on my success.
Since that cake, I have made many buttercreams, sometimes trying different recipes (the Silk Meringue Buttercream was fabulous), different flavours (pear, chocolate, banana), and gracing different cakes (cupcakes, big cakes, white, chocolate, etc.). I mostly use “The Cake Bible” by Rose Levy Beranbaum. Her recipes are very detailed and I have always had excellent results.
When my friend Annie asked me to consult on cupcakes for her wedding, I quickly volunteered to make the cupcakes myself. An outside wedding in the middle of the summer would be tricky, so I did some research, looking for the sturdiest buttercream that would hold up on a warm day. The mousseline buttercream fit the bill. Annie’s Mom, Janette, had some doubts about just having plain old cupcakes at her only daughter’s wedding, until I took some over for a tasting. Janette & I had a wonderful afternoon, tasting cupcakes, and experimenting with the sugared violets that she made for the wedding. They looked gorgeous and tasted even better!
My procrastination really got the best of me that weekend. Mousseline buttercream can be made ahead of time and stored 10 days in the fridge or up to 8 months frozen. Do you think I made one batch of that stuff ahead of time? Not one! Another quirk of buttercream is this: “If the butter is too soft or the room too hot, what could have been a satin-smooth cream breaks down into a grainy puddle.” The week before Annie’s wedding was very hot and humid and my parents didn’t have air conditioning in their house. This created a huge problem, especially since I was using the oven to bake cupcakes non-stop. I ended up dragging my KitchenAid around to three neighbour’s kitchens, air conditioning mandatory. In the end, the cupcakes looked lovely, and thanks to my sister and brother-in-law, they were iced and ready on time. I will never under-estimate how long it takes to ice that many cupcakes again! Oh, who am I kidding….
1 lb. unsalted butter, softened but not too soft
3/4 c. + 1/4 c. white sugar
1/4 c. water
5 or 6 egg whites (use a glass measuring cup to measure 5 oz.)
1/2 +1/8 t. cream of tartar
2-3 oz. liqueur (Grand Marnier, Banana Liqueur, Poire Williams, etc.), optional
In a mixing bowl, beat the butter until smooth and creamy and set aside in a cool place. Have ready a heatproof glass measuring cup near the stove.
In a small heavy saucepan, heat 3/4 c. sugar and the 1/4 c. water, stirring constantly, until the sugar dissolves and the mixture is bubbling. Stop stirring and reduce the heat to low. Attach a candy thermometer to the side of the saucepan and keep an eye on the temperature.
In the bowl of your KitchenAid, beat the egg whites until foamy, add the cream of tartar, and beat until soft peaks form when the beater is raised. Gradually beat in the remaining 1/4 cup of sugar until stiff peaks form when the beater is raised slowly. Increase the heat and boil the syrup until the thermometer registers between 248 and 250 degrees (the firm-ball stage). Immediately transfer the syrup to the glass measuring cup to stop the cooking.
Working quickly, pour a small amount of syrup over the egg whites with the mixer off. Immediately beat at high speed for 5 seconds. Continue doing this with the remaining syrup. For the last addition, use a rubber scraper to remove the syrup clinging to the glass measuring cup. Lower speed to medium and continue beating up to 2 minutes or until cool. If not completely cool, continue beating on lowest speed.
Beat in the butter at medium speed 1 tablespoon at a time. At first the mixture will seem thinner but will thicken beautifully by the time all the butter is added. If at any time the mixture looks slightly curdled, increase the speed slightly and beat until smooth before continuing to add more butter.
Lower the speed slightly and drizzle in the liqueur. Add food colouring now, if desired. Place in an airtight bowl. Re-beat lightly from time to time to maintain it’s silky texture. Buttercream becomes spongy if left standing too long. Don’t ever beat a buttercream that has been chilled and hasn’t come back up to room temperature.
Makes 4 1/2 c. of buttercream, enough to fill and frost a 9-inch layer cake or lots of cupcakes!