01 -
Line a plate with parchment paper and spread your pistachio cream into a thick layer. If your spread is already quite thick, you can also just drop spoonfuls onto the paper to create dollops. Pop it in the freezer for at least an hour until it's completely solid. If you went with the sheet method, cut it into small squares once frozen and return them to the freezer.
02 -
Line a cutting board or plate with parchment paper - this is where you'll place your cookie dough balls to chill later. In a small bowl, mix together the flour, cornstarch, baking powder, baking soda, and salt until well combined. Set this dry mixture aside.
03 -
In a large bowl, whisk together the melted (but cooled) butter with both the brown and white sugars until they're well blended. Add the egg and vanilla, then whisk until the mixture becomes smooth and looks a bit thicker - this usually takes about a minute of good whisking.
04 -
Add the flour mixture to your wet ingredients and gently whisk until just barely combined - you should still see a few flour spots. Then toss in your chopped chocolate and pistachios, switching to a spatula to fold everything together. Mix just until no dry flour remains - overmixing will make tough cookies!
05 -
Using a 4-tablespoon cookie scoop (or just a 1/4 cup measure), scoop out balls of dough and place them on your parchment-lined board. Pop the whole thing in the fridge for about an hour until the dough balls firm up enough to handle easily.
06 -
Preheat your oven to 350°F and line a baking sheet with parchment paper. Take your chilled dough balls out of the fridge and grab your frozen pistachio cream from the freezer.
07 -
Take a ball of dough and press it flat in your palm. Place a chunk (or a few small pieces) of the frozen pistachio cream in the center - about 3-4 squares if you cut it up. Carefully fold the cookie dough around the filling, making sure to completely seal it inside so nothing leaks during baking.
08 -
Place your stuffed cookies on the baking sheet, leaving about 2 inches between them for spreading. Press a few extra pieces of chocolate chunks, chopped pistachios, and tiny bits of frozen pistachio cream on top of each cookie for that beautiful bakery-style look.
09 -
Slide the cookies into the oven and bake for 11-12 minutes, just until the edges look set but the centers still look soft and slightly underdone. As soon as they come out, sprinkle them with a little flaky salt while they're still hot.
10 -
Let the cookies cool on the baking sheet for about 5 minutes - they're too fragile to move right away. For the ultimate experience, enjoy them while they're still warm and the pistachio center is gloriously gooey. If you wait until they cool completely, the filling will firm up, which is still delicious but a different experience!