Prepare Pistachios: Roast 1 cup of shelled pistachios at 350°F (175°C) for 8-10 minutes. Let cool, then blend into a smooth paste.
Mix Ice Cream Base: In the Ninja Creami container, combine 1 cup heavy cream, 1 cup whole milk, and ½ cup granulated sugar (adjust to taste). Optionally, add 1 tsp vanilla extract.
Add Pistachio Paste: Stir the pistachio paste into the ice cream base until well combined.
Freeze: Follow Ninja Creami instructions to churn and freeze the mixture until creamy, about 15-20 minutes. Serve immediately and enjoy your pistachio ice cream!
