Preheat the oven to 350°F. Line two baking sheets with parchment paper.
Pulse the pistachios in a food processor until finely ground. Set aside.
In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream together butter, brown sugar, and white sugar until light and fluffy.
Add egg yolks, vanilla extract, and ground pistachios, and mix until pale and fluffy.
Gradually add dry ingredients to wet ingredients and mix until combined.
Fold in chopped dark chocolate and pistachios with a rubber spatula.
Scoop dough onto prepared baking sheets and bake for 10-12 minutes.
Let cookies cool on the baking sheet for five minutes, then transfer to a wire rack to cool completely.
After baking, use a large circular cookie cutter to shape cookies and sprinkle with extra chocolate, pistachios, and flaky sea salt. Enjoy!