Chocolate Chunk Cookies

In the bowl of an electric mixer, beat the butter and both sugars for 3 minutes, or until light, fluffy, and cafe au lait-colored (use high speed on a hand mixer and medium speed on a stand mixer). Scrape down the sides and bottom of the bowl as necessary. Add the vanilla and eggs and beat for 2 minutes more. Scrape down the bowl. Add the salt and baking soda and beat briefly until evenly combined. Add the flour and both chocolates, and mix on low speed until the flour is completely blended and the chocolate is evenly distributed throughout the dough.

Cover the bowl with plastic wrap or scrape the dough into an airtight container and let rest in the refrigerator until firm, a few hours. (Alternatively, if you don't want to wait, form the dough into balls on the baking sheet as instructed below and chill in the fridge until firm, about 30 minutes.)

Preheat the oven to 350°F (175°C) and set a rack in the middle position. Line a 13 x 18-in (33 x 46-cm) baking sheet with parchment paper.

Drop the dough in firmly packed 1.5-tablespoon balls onto the prepared baking sheet, spacing them about 2 inches apart. (I use a #40/1.5-T cookie scoop with a wire trigger.) Bake for 11 to 13 minutes, until golden around the edges but still soft and pale in the center. Let cool for a few minutes on the baking sheet, then transfer to a wire rack to cool completely. Repeat with remaining cookie dough. The cookies can be stored in an airtight container at room temperature for up to 3 days.