Italian : This stable and fluffy buttercream is made with an Italian meringue base (heated sugar syrup is beaten into egg whites until stiff peaks form). Small pieces of butter are then mixed in to make the frosting.
How to Make Perfect Italian Meringue Buttercream: Step-by-Step
The Creaming Method - Jenni Field's Pastry Chef Online The speed at which you cream the ingredients and the length of time you cream your ingredients and the temperature of your ingredients will all effect [sic] the final product.
Martha Stewart's Grand Marnier Italian Buttercream Frosting
Italian Buttercream- cake boss: this stuff tastes amazing! Definitely time consuming, however. The recipe states the 'cool down' stage joule take mins. Mine took more like an hour. But in the end it turned out great!