The Food Lab's Chocolate Chip Cookies

Ingredients

• 8 ounces unsalted butter
• 1 standard ice cube
• 10 ounces all-purpose flour
• 3/4 teaspoon baking soda
• 2 teaspoons Diamond Crystal kosher salt or 1 teaspoon table salt
• 5 ounces granulated sugar
• 2 large eggs
• 2 teaspoons vanilla extract
• 5 ounces dark brown sugar
• 8 ounces semisweet chocolate, roughly chopped with a knife into 1/2- to 1/4-inch chunks
• Coarse sea salt, for garnish

Directions

1. Melt the butter in a medium saucepan set over medium-high heat. Cook it for about 5 minutes, keeping the pan moving in gentle circles, until the milk solids start to brown and the butter smells toasty. Take the pan off the heat and keep swirling for about 15 seconds more, until the butter turns a deep brown. Pour it into a medium bowl, whisk in the ice cube, then move the bowl to the refrigerator until fully cooled, about 20 minutes, whisking now and then. If you want to speed things along, whisk the bowl over an ice bath instead.
2. While the butter cools, combine the flour, baking soda and salt in a large bowl with a whisk. Add the granulated sugar, eggs and vanilla extract to the bowl of a stand mixer fitted with the whisk attachment. Beat on medium-high speed until the mixture is pale brownish-yellow and drops from the whisk in thick ribbons when you lift it, about 5 minutes.
3. Switch the mixer to the paddle attachment. Once the brown butter has cooled and is just beginning to look opaque again, with the edges starting to firm, add the brown sugar and cooled brown butter to the egg mixture in the stand mixer. Mix on medium speed for about 15 seconds, just to bring it together. Add the flour mixture and mix on low speed until it is only barely incorporated and a little dry flour is still visible, about 15 seconds. Add the chocolate and continue mixing on low speed until the dough comes together, about 15 seconds longer. Move the dough to an airtight container and refrigerate it at least overnight and up to 3 days.
4. When it is time to bake, set the oven racks in the upper-middle and lower-middle positions and heat the oven to 325 degrees F. With a 1-ounce ice cream scoop or a spoon, portion the cookie dough onto a nonstick or parchment-lined baking sheet. Each mound should be about 3 tablespoons, with 6 to 8 dough balls on each sheet. Split each ball in half to expose a craggy interior, then press the halves back together with those rough sides facing out. Bake until the edges are golden brown and the centers are still soft, 13 to 16 minutes, turning the pans front to back and switching them from top to bottom midway through.
5. Take the baking sheets out of the oven. While the cookies are hot, add a very light sprinkle of coarse salt and press it in gently so it sticks. Cool the cookies on the sheets for 2 minutes, then move them to a wire rack to finish cooling.
6. Continue shaping, baking, salting and cooling the rest of the cookie dough the same way. Once the cookies are completely cool, store them at room temperature in an airtight container, plastic bag or cookie jar for up to 5 days.