Ever so slightly adapted from epicurious.com, this is my go-to buttercream recipe. The little bit of extra time it takes to make the meringue is worth every second.
4 large egg whites, room temperature
Generous 1/4 teaspoon salt
2/3 cup water
1 1/4 cups plus 1 Tablespoon sugar, divided
2 cups unsalted butter, room temperature, cut into pieces
2 teaspoons vanilla
Place water and 1 1/4 cups sugar in medium saucepan and bring to boil, making sure all sugar is dissolved. Let boil until the syrup reaches 240 degrees F on candy thermometer.
Meanwhile beat egg whites until frothy, then slowly add the remaining 1 Tablespoon of sugar. Beat until soft peaks form.
Slowly pour the hot syrup along the side of the bowl and into the egg whites mixture. Beat on high, scraping sides of bowl until meringue is cool to the touch. This takes me about 10-15 minutes with this plastic bowl. A metal bowl may hold the heat longer.
Once the meringue is cool, and it is very important that you are patient enough for it to cool, thoroughly incorporate the butter a piece at a time.
Continue beating until all the butter is added and buttercream is smooth and fluffy. Add vanilla and beat another minute or two. Frost your favorite cake and prepare yourself for rave reviews.
This recipe will frost 48 Guinness Cupcakes like this:
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