01 -
Start by preparing your pistachio cream filling. Line a small plate with parchment paper and spread the pistachio cream into a thick, even layer. If your pistachio spread is already quite thick, you can also use a spoon to create small dollops directly on the parchment. Place in the freezer for at least an hour (or overnight) until completely solid. If you went with the sheet method, once frozen, cut it into small squares with a knife and return to the freezer until you're ready to stuff the cookies.
02 -
In a medium bowl, whisk together the flour, cornstarch, baking powder, baking soda, and salt until well combined. The cornstarch is our secret weapon here - it helps create that perfect tender cookie texture. Set this mixture aside while you prepare the wet ingredients.
03 -
In a large mixing bowl, combine the melted and cooled butter with both brown and granulated sugars. Whisk vigorously until the mixture becomes smooth and the sugars are well incorporated. Add the room temperature egg and vanilla extract, then whisk again until the mixture becomes thick and glossy - this helps create that beautiful cookie texture.
04 -
Gradually add the dry ingredient mixture to your wet ingredients, whisking gently until just barely combined - you should still see a few flour patches. Switch to a spatula and add the chopped chocolate and pistachios. Fold everything together just until no dry flour remains visible. Be careful not to overmix - that's the key to soft, tender cookies!
05 -
Line a cutting board or plate with parchment paper. Using a 4-tablespoon cookie scoop (or about 1/4 cup measure), portion out rounds of dough onto the lined surface. Place the entire board in the refrigerator and chill the dough balls for about an hour until they're firm enough to handle easily.
06 -
Preheat your oven to 350°F and line a baking sheet with parchment paper. Take a chilled dough ball and flatten it gently with your fingers into a disk. Place 3-4 pieces of the frozen pistachio cream in the center, then carefully fold the cookie dough around it, sealing it completely. Place the stuffed cookies on your prepared baking sheet, leaving about 2 inches between each for spreading. Press a few extra chocolate chunks, pistachio pieces, and tiny bits of frozen pistachio cream on top for a beautiful finish.
07 -
Slide your cookies into the preheated oven and bake for 11-12 minutes - they should have golden edges but still look slightly underdone in the center. This is exactly what you want for that perfect gooey middle! Immediately after removing from the oven, sprinkle each cookie with a pinch of flaky sea salt. Let them cool on the baking sheet for 5 minutes before transferring to a wire rack. Enjoy them warm for an incredible molten pistachio center, or let them cool completely for a more set filling.