Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

Cream together the softened butter and granulated sugar in a large mixing bowl until light and fluffy, about 3-4 minutes.

Add the vanilla extract to the butter and sugar mixture and mix on low speed until evenly incorporated.

Gradually sift in the all-purpose flour while mixing on low speed, then add the chopped unsalted pistachios until just combined.

Scoop out small balls of dough and place them on the prepared baking sheet, spaced evenly.

Flatten each dough ball slightly with your palm or the bottom of a glass.

Bake for approximately 15-20 minutes, until the edges are golden brown and the centers are slightly soft.

Let the cookies cool on the baking sheet for about 5 minutes, then transfer to a wire rack to cool completely.