Beat butter, brown sugar, and granulated sugar until fluffy. This will give the cookies a melt-in-your-mouth texture.

Mix in the egg and vanilla until fully blended.

Combine flour, baking powder, baking soda, and salt in a separate bowl. Add to wet ingredients and mix until no streaks of flour remain.

Fold in pistachio cream and chopped pistachios. Avoid overmixing to maintain pretty green swirls.

Refrigerate the dough for 30 minutes to enhance flavor and shape retention.

Preheat oven to 350°F. Scoop dough onto a baking sheet and bake for 9-11 minutes until edges are set but centers are slightly glossy.

Let cookies cool, then pair with pistachio cream for sandwich cookies or drizzle on top for extra flavor.