Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until fluffy.
Add in the pistachio pudding mix, eggs, and vanilla extract. Mix until well combined.
In a separate bowl, whisk together the flour, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients and stir just until combined.
Fold in the chopped pistachios and white chocolate chips.
Drop dough by rounded tablespoonfuls onto the prepared baking sheet, spacing about 2 inches apart.
Bake for 10-12 minutes, or until the edges are lightly golden and centers are set.
Allow cookies to cool on the pan for a few minutes before transferring to a wire rack to cool completely.