Begin by blanching 2 cups of shelled unsalted pistachios in boiling water for 2 minutes. After blanching, drain and cool them under cold running water, then gently rub the nuts to remove their skins.

In a high-speed blender, combine the blanched pistachios with 2 cups of whole milk, blending on high until smooth, about 2 minutes.

Transfer the blended mixture into a container and refrigerate overnight.

If desired, strain the chilled mixture through cheesecloth into a large bowl to ensure a velvety finish.

In a saucepan over medium heat, gently heat the strained pistachio-milk mixture. If thicker gelato is desired, mix 1.5 tablespoons of corn starch with a little milk until dissolved, then whisk into the warm mixture, stirring constantly for about 6 minutes.

Remove from heat and stir in the remaining milk, 0.67 cups of sugar, just a pinch of salt, and any optional extracts if using. Mix well, then add 1 cup of heavy cream.

Chill the combined mixture in the refrigerator for several hours before freezing.

Pour the cold mixture into your ice cream maker and churn according to the manufacturer’s instructions, adding optional ½ cup of coarsely ground pistachios as it starts to set.