In a medium saucepan, combine the milk, cream, sugar, cornstarch, and salt.
Heat the mixture over medium heat, whisking constantly until it begins to thicken (about 5-7 minutes).
Once thickened, remove from heat and stir in the chopped pistachios, vanilla extract, and butter if desired.
Pour the pudding into serving dishes and allow it to cool to room temperature.
Refrigerate for at least 2 hours to set before serving.
Notes
Make Ahead: Pistachio pudding can be prepared ahead of time and stored in the refrigerator for up to 3 days. It will stay fresh and creamy when covered tightly.
Customizing the Flavor: While pistachio is the main flavor, you can enhance the taste by adding a splash of almond extract or a few more chopped pistachios for added crunch and flavor.
Serving Suggestions: Serve chilled, topped with whipped cream or a sprinkle of extra chopped pistachios for a decorative touch. It also pairs well with a side of fresh berries or shortbread cookies.
Allergy-Friendly Options: To make the pudding dairy-free, substitute the milk and cream with almond or coconut milk and use a dairy-free butter alternative.
Storage Tips: Keep the leftover pudding in an airtight container in the fridge. If you want to keep it longer, you can freeze the pudding for up to 2 months. Thaw it in the refrigerator and whisk before serving.