1 cups walnut – coarsely chopped, toasted and cooled
12 ounces semisweet chocolate – coarsely chopped
3 cups all-purpose flour
2 teaspoons cornstarch
1 teaspoons baking soda
0.5 teaspoons baking powder
0.75 teaspoons fine sea salt
1 cups unsalted butter – softened
1 cups light brown sugar – packed
0.5 cups granulated sugar
2 large egg
2 teaspoons vanilla extract
Instructions
Line 2–3 baking sheets with parchment paper. Toast the walnuts in a dry skillet over medium heat, stirring often, until fragrant and lightly darkened, 5–7 minutes. Transfer to a plate to cool completely, then coarsely chop if not already chopped.
Coarsely chop the semisweet chocolate into chunky pieces and set aside.
In a medium bowl, whisk together the all-purpose flour, cornstarch, baking soda, baking powder, and fine sea salt.
In a large bowl or stand mixer, beat the softened unsalted butter, light brown sugar, and granulated sugar on medium speed until creamy and slightly lightened, 2–3 minutes. Scrape down the bowl.
Beat in the eggs one at a time until smooth, then mix in the vanilla extract until combined.
Add the dry ingredients to the butter mixture and mix on low just until a few dry streaks remain.
Fold in the chopped chocolate and toasted walnuts until evenly distributed and no dry flour remains. Do not overmix.
Cover the bowl and chill the dough until firm to scoop, 1–2 hours.
Preheat the oven to 375°F (190°C). Using a 3-tablespoon scoop (about 2 ounces/55–60 g), portion the dough onto the prepared sheets, spacing about 2.5 inches apart. Keep any remaining dough chilled between bakes.
Bake one sheet at a time until edges are deep golden and set, tops are puffed and lightly cracked, and centers still look soft, 11–13 minutes, rotating the sheet halfway through.
Cool the cookies on the sheet for 5–10 minutes to set, then transfer to a wire rack to cool until just warm, about 20 minutes. Repeat with remaining dough.