Swiss Meringue Buttercream

Lightly wipe the bowl of a stand mixer, a whisk and the mixer whisk attachment with white vinegar to remove all traces of grease.

Measure sugar into the mixer bowl using a food scale (750 grams is roughly 4 cups). Add the egg whites into the sugar and position the candy thermometer into the mixer bowl. Set aside.

Cut butter into cubes about one tablespoon in size and set them near the standing mixer so that the butter can come to room temperature while you prepare the meringue.

Add about an inch of water to a small pot. Place the mixer bowl onto the top of the pot and place the pot on the stove over medium-high heat. Whisk the mixture constantly until it reaches 160°F. Remove the candy thermometer and place the mixer bowl on the standing mixer. Use the whisk attachment and whip until mixture is thick, glossy, and the outside of the bowl is only slightly warmer than body temperature. This will take about 15-20 minutes. Switch over to the paddle attachment and turn to medium speed. Add butter one cube at a time about five seconds apart, allowing each to mix in.

Once all the butter is incorporated, increase speed to medium-high and whip until the icing is a silky, smooth texture. It will look curdled along the way, but keep whipping! Once it has reached that silky texture, add vanilla and salt (and other flavorings if desired) and mix well.

If desired, add a few drops of icing color to tint the icing.

Note: Here are a few variations on flavor that I’ve tried. There are, of course, countless others.
– Espresso buttercream: For every 5 cups of buttercream, combine 2 tablespoons of hot water and 1 1/2 tablespoons of instant espresso in a small bowl. Add to buttercream at the end when you add the vanilla and whip until thoroughly combined.
– Raspberry buttercream: For every 5 cups of buttercream, add 1 cup fresh raspberries and mix until desired coloring is achieved.
– Blackberry buttercream: For every 5 cups of buttercream, add 2 cups fresh blackberry puree and mix well.
– Almond buttercream: Substitute 1 tablespoon almond extract for one of the tablespoons of vanilla extract in the last step.

Adapted from Sweetapolita.