Swiss Meringue Buttercream II (Less Butter)

[Updated 2011-03-30]

Makes about 4 cups (enough to frost 24 cupcakes)

Ingredients

• 4 large egg whites
• 1 cup sugar
  
• 1 1/4 cup (2 sticks + 1/2 a stick) unsalted butter, slightly softened and cut into 1 tablespoon portions
• 2 teaspoons vanilla extract

Directions

1. Put egg whites and sugar into the top of a double boiler over a pan of simmering water. Whisking constantly. Tip: Remove the upper vessel of the double boiler from the steam source periodically while continually whisking when it gets too hot to touch. When the upper vessel is cool enough to touch, but still very warm, return upper vessel to steam.
2. Cook egg white and sugar mixture until sugar has dissolved and mixture is hot to the touch (about 160 degrees). Tip: Using your fingers, pinch a portion of the mixture. The mixture should fill smooth and not grainy.
3. Pour heated egg whites into the bowl of an electric mixer fitted with the whisk attachment. Beat egg white mixture on high speed until fluffy and cooled, from 5-7 minutes. Tip: The egg white mixture should form stiff peaks.
4. Switch to the paddle attachment. With mixer on medium-low, add butter two tablespoons at a time, beating well after each addition. Tip: While adding the butter, the mixture may begin to break. This is OK. Continue adding in the remaining butter.
5. Increase speed to medium-high; continue beating until frosting appears thick, about 3 minutes. Reduce speed to low; add vanilla extract and continue beating 2 minutes to eliminate air bubbles. Tip: At this point, the mixture should appear thick and continue to become more frosting like. If this does not happen after a few minutes of mixing, you may need to add additional butter. If additional butter is needed, add the butter 2 tablespoons at a time (in 1 tablespoon portions) and mix well before adding each 2 tablespoon portion. Check after each 2 tablespoon portion addition if the mixture is beginning to thicken. If so, there is no need to add additional butter.

Note:

When doubling the recipe, use the following ingredient list:

• 8 large egg whites
• 1 3/4 cup sugar
  
• 2 1/2 cup (5 sticks) unsalted butter, slightly softened and cut into 1 tablespoon portions
  
• 3 teaspoons vanilla extract

Credits:
How to Eat a Cupcake blog