Begin by placing 1 cup of raw unsalted pistachios into a food processor. Add 1/4 cup of sugar and blend until the mixture forms a smooth paste, about 1-2 minutes. Set this pistachio paste aside for later use.

In a medium mixing bowl, whisk together 4 egg yolks and 1/4 cup of sugar until the mixture becomes fluffy and pale, typically taking about 3-4 minutes of vigorous mixing.

In a saucepan, combine 1 cup of whole milk, 1 cup of heavy cream, 1/4 cup of sugar, and 1/2 teaspoon of salt, stirring gently until it reaches a temperature of 180°F.

Take a ladle of the hot dairy mixture and slowly whisk it into the egg yolk mixture to temper. Once combined, pour it back into the saucepan.

Reduce the heat to low and stir the custard mixture continuously for about 5 minutes until it thickens enough to coat the back of a spoon.

Remove from heat and stir in the remaining cup of heavy cream, 2 teaspoons of vanilla extract, and the prepared pistachio paste. Mix well until fully combined.

Transfer the mixture into a shallow container, cover with plastic wrap, and refrigerate overnight or for at least 3-4 hours.

Pour the chilled mixture into an ice cream maker and churn according to manufacturer's instructions, usually taking about 20-25 minutes.

After churning, transfer the ice cream to an airtight container and freeze for at least 6 hours until firm. Serve with optional toppings.