2 c unsalted butter, softened but cool (65F)
1 c sugar
1/4 c water
5 large egg whites
1/2+1/8 tsp cream of tartar
3 oz fruit syrup (strawberry, raspberry, mango) or 2 tsp. flavoring (vanilla extract, almond extract)
In a mixing bowl, beat the butter until smooth and creamy and put to a cool place. Have ready a heatproof glass measure near the range.
In a small nonstick saucepan, heat 3/4 c sugar and 1/4 c water, stirring constantly, until the sugar dissolves and the mixture is bubbling. Stop stirring and reduce the heat to low.
In another mixing bowl, 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 c sugar until stiff peaks form when the beater is raised slowly.
Increase the heat and boil the syrup until a thermometer registers 248 to 250F.
Immediately transfer the syrup to the glass measure to stop the cooking.
Beat the syrup into the whites in a steady stream.
At the end, use a scraper to remove the syrup clinging to the glass measure.
Lower speed to medium and continue beating until the mixture is cool. (This took me several minutes.)
Beat in the butter at medium speed 1 tablespoon at a time.
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 fruit syrup or flavorings.
Store in airtight bowl.
Rebeat from time to time to restore texture.
This buttercream will keep for 2 days at room temperature, 10 days refrigerated and 8 months frozen.
Allow to come to room temperature before rebeating or it will break down irretrievably
Pairs Well With
adapted from The Cake Bible
This is my favorite frosting for cakes. I like to flavor mine with espresso powder dissolved in a tiny bit of water. It's delicious on a chocolate cake!
It takes practice to make this, but don't give up