Italian Butter Creme Frosting

Amy sent me this recipe from her Mom who said it was heavenly! Her mom's advice and comments on her experience making this are included with the directions for added help. This would be so good on cupcakes, and I love that there is a lemon option too. yum!

Italian Butter Creme Frosting

1 1/4 cups sugar
2/3 cup water
5 pasteurized egg whites (the kind sold refrigerated in a carton)
Pinch of cream of tartar
1 lb. (4 sticks) unsalted butter, chilled
1 tsp.pure vanilla extract

In a pot over medium heat, bring the sugar and 2/3 cup water to a boil. Continue boiling until syrup reaches 238* F on a candy thermometer (soft-ball stage). Meanwhile, place egg whites in the bowl of a stand mixer fitted with the whisk attachment, and beat on low speed until foamy. Add the cream of tartar, and beat on medium-high speed until stiff but not dry; do not overbeat. With the mixer running, or with a second adult operating a hand-mixer, add the hot syrup from the pot to the egg whites, beating on high speed until the mixture is no longer steaming, or about 3 minutes.( My advice.....Don't rush this step, it may take 5 minutes so make sure it is really cooled down before you go on ) Add the butter bit by bit, beating until spreadable, approximately 3 to 5 minutes; (I followed the recipe exactly and felt there was too much butter. I would use 3 sticks of butter instead of 4 next time) beat in vanilla. If the icing curdles or separates, keep beating until it is smooth. ( It shouldn't separate if you have been patient when cooling down but mine did and after about a minute it got fluffy again)

-Lemon Buttercream: Substitute lemon juice for the vanilla. Some grated lemon peel could also be added.

-Mocha Buttercream: Omit vanilla and substitute ½ teaspoon of instant coffee dissolved in 1 1/2 teaspoons of water or milk