Ingredients

The following ingredients have 12 Servings
  • 6 large egg yolks (at room temperature)
  • 1/2 cup water
  • 1 cup granulated sugar
  • Generous pinch salt
  • 4 sticks (1 lb) unsalted butter (softened to room temperature, cut into pieces)
  • 1/3 cup roasted unsalted pistachio butter or paste

Instruction

  • In the bowl of a stand mixer fitted with the paddle attachment or in a large bowl using a hand mixer, beat the yolks until light in color, 3 to 5 minutes.
  • In a small saucepan over high heat, combine the water, sugar, and salt, stir constantly to dissolve the sugar.
  • Once the sugar mixture comes to a boil stop stirring. Continue to boil until the mixture registers 240°F (115°C) on a candy thermometer, 5 to 10 minutes.
  • Turn the mixer on low, and carefully–carefully, I say!–slowly dribble in the sugar syrup, avoiding the spinning beater. Once the sugar syrup is incorporated, bump the speed up to medium-high and continue beating until the mixture is completely cool, about 5 minutes.☞TESTER TIP: If the egg mixture is even the least bit warm, it'll melt the butter, and you'll be staring at a puddle--of frosting and your tears.
  • Once the mixture is cool, add the butter, a knob at a time, beating until the buttercream is luscious and smooth, about 5 minutes.
  • Spoon in the pistachio butter and whir to combine until silky smooth, about 1 minute.