Best buttercream ever

This buttercream icing does require a stand mixer & a candy thermometer to make, but it is simply the best tasting icing you'll ever prepare!  Be sure to read the whole recipe through before starting to understand the timing right.

Yield:  9 cups

Ingredients:

2 cups Sugar

1 cup Water

1 cup Egg whites (about 7 eggs)

1/2 tsp Salt

1 pinch Cream of Tartar

3 cups Unsalted butter, room temperature

1 Tbsp Vanilla extract

Method:

1. Combine sugar and water in medium saucepan and place over medium high heat.  Stir until sugar dissolves, then turn to high heat and place candy thermometer in syrup.  Allow sugar water to boil and heat until the temperature reads 238 degrees F.

2.  Meanwhile, combine egg whites, salt and cream of tartar in bowl of stand mixer fitted with whisk attachment.  When sugar syrup reaches 230 degrees, begin whipping egg mixture on high.  With the mixer running on high, carefully and slowly pour the hot sugar syrup down the side of the mixer bowl in a steady stream (congrats! you just made a stabilized meringue!) Continue to let the meringue beat on high until the bowl has reached room temperature.  Depending on how hot your kitchen is, this could take 10 - 20 minutes. 

3.  Meanwhile, cut the butter into tablespoon servings.  When the mixer bowl has reached room temperature, begin to add butter, one tablespoon at a time to the meringue with the mixer still running on high.  Once all the butter has been added, it will seem as if the buttercream has curdled- give it a minute, it will come together.  Once the buttercream is smooth, beat in the vanilla. 

4.  Store in airtight container in refrigerator. Buttercream will become solid after it's chilled, but can be brought back simply by using the whisk attachment on the stand mixer and beating on high.