Thin, Crisp Chocolate Chip Cookies

Adapted from Pastry Love: A Baker's Journal of Favorite Recipes by Joanne Chang

I found the original recipe yielded a nice cookie but they were a little thicker than I was expecting and while delicious, the cookies weren't entirely crisp. If you want to stick to the original recipe, use 2 cups (280g) of flour. You do want to make sure you bake these cookies on the upper rack of the oven, so they don't get too dark on the bottoms before the tops are browned. And be sure to watch them like a hawk during the last few minutes of baking; the baking times are guidelines so check the cookies a few minutes before the listed baking times and remove the cookies from the oven at the moment when they're gently browned all the way across the top. You can either buy superfine sugar (which is sometimes called Baker's sugar or in French, it's sucre en poudre, or make it yourself by pulsing granulated sugar in a blender or food processor until the crystals are very fine, about half the size they originally were.

In the U.S., the extra-dark Guittard chips work well. In France (and in Europe), Cacao-Barry makes chocolate chips, although they're smaller than the larger American chips. (They're available at G. Detou in Paris.) Supermarket-style chocolate chips are formulated not to melt when baked, so they may be of interest to you if you like those slightly toothsome chunks of chips in your cookies, but you can use hand-chopped chocolate chunks, in place of them.

8 ounces (225g) unsalted butter, at room temperature
1 cup (200g) superfine sugar, (see headnote)
1/2 cup (100g) firmly-packed light brown sugar
1 large egg, at room temperature
3 tablespoons (45g) water
2 teaspoons vanilla extract
1 3/4 cups (245g) flour
1 1/4 teaspoon flaky sea salt or kosher salt, (if using Morton's kosher salt, use 3/4 teaspoon)
1 teaspoon baking soda
1 1/2 cups (280g, 10 ounces) bittersweet or semisweet chocolate chips

In a stand mixer fitted with the paddle attachment, or by hand with a wooden spoon or spatula in a bowl, beat the butter and sugars on medium speed until light and creamy, about 5 minutes.
Stop the mixer and scrape down the sides with a rubber spatula, reaching down to the bottom of the mixer bowl. Beat in the egg, WATER, and vanilla.
In a medium bowl, mix together the flour, salt, and baking soda. Add the chocolate chips, and toss in the flour mixture. With the mixer on low speed, stir in the flour and chocolate chip mixture until thoroughly combined. Cover the bowl (or transfer to a smaller container, and cover) and refrigerate the dough at least 3 to 4 hours, or overnight.
To bake the cookies, preheat the oven to 350ºF (180ºC). Line two baking sheet with parchment paper. Arrange the dough, formed in 1 1/4-inch (1/4 cup, 45g) balls on the baking sheet, spaced at least 3-inches (8cm) apart. (They will spread, so expect to get 5 or 6 on a standard baking sheet.) Press the cookies down slightly with your hand and bake until the cookies have spread and just until there are no light patches across the center, rotating the baking sheet(s) midway during baking so they bake evenly. They'll take about 13-14 minutes, but best to check the cookies a few minutes before and use the visual clues, rather than adhere to strict baking time, to get them just right.
Remove the cookies from the oven and let cool for 5 minutes. Transfer the cookies to a wire rack and cool completely.

Notes

Storage: The dough can be refrigerated up to four days, or frozen for up to three months. The cookies will keep in an airtight container for up to three days but are best the day they are baked.