1 cup all-purpose flour
1/2 teaspoon baking soda
1/4 teaspoon salt, preferably fine sea salt
8 tablespoons (1 stick) unsalted butter, softened
1/4 cup dark brown sugar
1/4 cup light brown sugar
1/4 cup granulated sugar
1 large egg
1 teaspoon vanilla extract
1 1/4 cups semisweet chocolate chips
Preheat the oven to 350 degrees F. Line a large, heavy rimmed sheet pan or cookie sheet (measuring 13 by 18 inches) with a length of ovenproof kitchen parchment paper.
For the dough, sift the flour, baking soda, and salt onto a sheet of waxed paper. Resift the flour mixture once more.
Cream the butter in the large bowl of a freestanding electric mixer on moderately low speed for 2 minutes. Add the dark brown sugar and beat for 1 minute. Add the light brown sugar and beat for 1 minute. Add the granulated sugar and beat for 30 seconds. Blend in the egg and vanilla extract. On low speed, add the sifted mixture in 2 additions, mixing just until the dry ingredients are incorporated. Scrape down the sides of the mixing bowl frequently with a rubber spatula to keep the dough even-textured. Work in the chocolate chips.
Scrape the dough onto the prepared baking pan, and spread it into a rough round a scant 1/4 inch thick. The dough mass/vague round should measure about 11 inches in diameter.
Bake the confection in the preheated oven for 15 minutes, then, using oven mitts to protect your hands, carefully remove the baking pan to a heatproof surface and rap lightly several times so that the dough falls/collapses. Return the confection to the oven and bake for 15 minutes longer or until deep golden on top, and completely set.
Cool the confection completely on a cooling rack. Carefully break the big cookie into craggy pieces. Store in an airtight cookie tin.
about two dozen pieces, depending on the size of the broken slabs
on baking day, or up to three days in advance, stored in an enclosed container
◊ sifting the dry ingredients twice develops the texture of the baked cookie
◊ fine sea salt creates the most flavorful dough
◊ the entire sheath of the cookie must be baked through or the interior may be pasty
◊ a wide outside band of the baked confection is crispy and the interior portion is chewy/tender, creating a confection of two textures