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

In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.

In a large mixing bowl, beat the softened butter and granulated sugar until light and fluffy.

Add the egg, orange zest, orange juice, and vanilla extract, mixing until well combined.

Gradually add the dry ingredients to the wet ingredients and mix until a soft dough forms.

Fold in the chopped pistachios until evenly distributed throughout the dough.

Scoop tablespoon-sized portions of dough and place them on the prepared baking sheet, leaving space between each cookie.

Gently flatten each dough ball slightly using your hand or the bottom of a glass.

Bake for 10–12 minutes, or until the edges are lightly golden.

Let the cookies cool on the baking sheet for a few minutes, then transfer them to a wire rack to cool completely