Step 1

This cookie dough requires at least 2 hours of chilling, but I prefer to chill the dough overnight. The colder the dough, the thicker the cookies.

Step 2

In a large bowl using a hand-held or stand mixer fitted with a paddle attachment, beat the butter, granulated sugar, and brown sugar together on medium high speed until fluffy and light in color. On high speed, beat in the egg and vanilla extract. Scrape down the sides and bottom of the bowl as needed.

Step 3

In a separate bowl, whisk the flour, cocoa powder, baking soda and salt together until combined. With the mixer running on low speed, slowly pour into the wet ingredients. Beat on low until combined. The cookie dough will be quite thick. Switch to high speed and beat in the milk, then the white chocolate chips. The cookie dough will be sticky. Cover dough tightly with aluminum foil or plastic wrap and chill for at least 3 hours and up to 3 days. Chilling is mandatory for this sticky cookie dough. I always chill mine overnight.

Step 4

Remove cookie dough from the refrigerator and allow to sit at room temperature for 10 minutes. If the cookie dough chilled longer than 3 hours, let it sit at room temperature for about 20 minutes. This makes the chilled cookie dough easier to scoop and roll.

Step 5

Preheat oven to 350°F (177°C). Line two large baking sheets with parchment paper or silicone baking mats. (Always recommended for cookies.) Set aside.

Step 6

Scoop and roll balls of dough, a heaping 1.5 Tablespoons of dough each, into balls. Arrange 2-3 inches apart on the baking sheets. The cookie dough is sticky, so don’t be afraid to wipe hands clean after every few balls of dough you shape.

Step 7

Bake the cookies for 11-12 minutes or until the edges appear set and the centers still look soft. Allow to cool for 5 minutes on the cookie sheet. During this time, I like to press a few more white chocolate chips into the tops of the warm cookies. (This is optional and only for looks.) The cookies will slightly deflate as they cool. Transfer to cooling rack to cool completely.

Step 8

Cover leftover cookies tightly and store at room temperature for up to 1 week.