Preheat the oven to 350°F/180°C. Line a cookie sheet with parchment paper or silicone baking mat.

In a large bowl, using a handheld or stand mixer beat the butter until creamy (30 seconds). Add sugar and beat until well combined (3-4 minutes).

Add eggs, pudding mix, and vanilla extract, and beat until the eggs are well incorporated.

In a separate bowl, combine the dry ingredients (flour, baking soda, and salt). Mix that with the wet ingredients until just combined.

Fold in the white chocolate chips, and the chopped pistachios.

Using a small cookie scoop (1 tablespoon size), scoop out cookie balls onto a cookie sheet 2 inches apart. Bake in a preheated oven for 12 minutes or until the bottom of the cookie is lightly browned.

Allow the cookies to cool for 2 minutes on the baking sheet, then transfer to a wire rack to cool completely.