1/2 cup (1 stick) unsalted butter at room temperature
1/2 cup granulated sugar
1/2 cup packed light brown sugar
1 large egg
1 teaspoon pure vanilla extract
1 1/4 cups all-purpose flour
1/2 teaspoon baking soda
1/4 teaspoon salt
1 1/2 cups dark chocolate chips
1 cup shelled pistachios coarsely chopped
Smoked sea salt for sprinkling
Put racks in the center and upper third of the oven and preheat the oven to 350°F. Line 2 baking sheets with parchment paper.
In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and sugars until pale and fluffy, about 4 minutes. Add the egg and beat for about 1 minute. Add the vanilla and beat until incorporated.
In a medium bowl, whisk together the flour, baking soda, and salt. Add this mixture all at once to the butter mixture. Beat on low speed until just incorporated. Beat in the chocolate chips and nuts.
Scoop the cookie dough, about 2 tablespoons per cookie, onto the prepared baking sheets, leaving about 2 inches in between each cookie. Sprinkle generously with smoked sea salt.
Bake until just golden brown, 10 to 12 minutes. Let the cookies cool on the pans for 5 minutes before transferring them to wire racks to cool completely. The cookies will last, well wrapped, at room temperature for up to 4 days . . . as if they’ll last that long.