Swiss Meringue Buttercream Frosting

  • Yield: 5 cups

Try flavoring your Swiss Meringue Buttercream Frosting with different extracts such as lemon or almond. Or try a little alcohol such as a dark rum or ouzo. Or just drink the rum and ouzo and don’t mess with perfection. —Libbie Summers

Ingredients

5large egg whites
1 1/2cups sugar
1 1/2pounds (6 sticks) butter, cut into chunks, at room temperature
1tablespoon vanilla extract

Instructions

  1. Fill a medium saucepan with 2 inches water and place over medium-low heat. Set a medium ovenproof bowl over the simmering water, making sure the bottom of the bowl doesn’t come into contact with the water. Put the egg whites and sugar in the bowl and whisk together until all the sugar crystals have dissolved. Pour the hot egg white mixture into the (room temperature) bowl of a standing mixer fitted with the whisk attachment. Whisk on high speed for 10 minutes, or until the meringue has doubled in volume, holds a stiff peak, and has cooled down. It’s important that the meringue is not warm, or it will melt the butter. Stick your finger down into the meringue to feel the temp—and get a taste!
  2. Remove the whisk attachment and replace it with the paddle attachment. Mix the butter into the cooled meringue, 1⁄2 cup at a time. It is important to beat just until the butter is incorporated into the meringue; try turning the mixer off and on to create a pulsing effect.
  3. Once all the butter has been incorporated, gradually increase the speed of the mixer to high, then continue to beat on high speed until the mixture is thick and fluffy and holds a stiff peak. (Don’t be alarmed. The mixture will get soft and limp and then it will perk right up in a minute or two.) Scrape down the bowl as needed. Reduce the speed to low and add the vanilla, then beat for 1 more minute on high speed.
  4. Leftover frosting will keep in an airtight container in the refrigerator for up to 3 weeks and in the freezer for up to 3 months. Thaw completely and rewhip before using

Note: Don’t be alarmed if your Swiss Meringue Frosting curdles, nothing is lost. The curdling is happening because the butter you added, was cooler than the meringue. Just keep beating and it will all come together.

Excerpted from Sweet and Vicious: Baking with Attitude, © 2014 by Libbie Summers. Reproduced by permission of Rizzoli New York.