4 cups (480 grams) 100% pure cane confectioners’ sugar, such as C&H® or Domino®, spooned into cup and leveled off, sifting not necessary
1 cup (240 ml) champagne, pink champagne or sparkling wine, I used Santa Margherita Prosecco
¼ teaspoon (1.25 ml) pure almond extract, such as Nielsen-Massey®, optional
½ cup (1 stick/113 grams) salted butter, at room temperature
½ cup (1 stick/113 grams) unsalted butter, at room temperature
1 cup (192 grams) organic palm shortening, such as Spectrum Organics®, at room temperature
Pink food coloring paste, all-natural, organic and kosher preferred such as ChefMaster®
Using an electric stand mixer fitted with paddle attachment, place confectioners’ sugar into work bowl. Meanwhile, in a small heavy saucepan over medium-high heat, bring champagne to a boil. Boil until reduced by half to ½ cup, about 8 to 10 minutes. Remove from heat.
Immediately and very carefully pour boiling champagne over confectioners’ sugar in a steady stream with mixer on low speed (stir). Increase mixer speed to medium and beat, scraping down sides of bowl with rubber spatula, until sugar dissolves, mixture is smooth and cooled to room temperature, about 4 minutes. Add almond extract, if using, and mix until well blended.
Add butter and shortening and beat on low (stir), scraping down sides of bowl as necessary, until creamy and almost fully incorporated, about 2 minutes. Gradually increase mixer speed to medium and continue beating until light and fluffy, scraping down the sides of bowl as necessary with rubber spatula, about 10 minutes. (Beating buttercream on low and medium speeds will prevent it from incorporating too much air causing air bubbles.) Tint buttercream with pink food coloring paste.