Mix dry ingredients. In a medium bowl combine the flour, cocoa powder, baking soda, and salt. Set aside.

Combine butter and sugars. In the bowl of a stand mixer with a paddle attachment, beat the butter and sugars together until they are light and fluffy, about 2 minutes.

Add the eggs and vanilla. Beat until just combined.

Add the dry ingredients. Beat on low until no dry bits of batter are visible. Be sure to scrape the bottom of the bowl.

Chill the dough. Cover your bowl with saran wrap and chill in the fridge for at least 1 hour and up to overnight.

Prep your tools. Preheat your oven to 350F. Line two baking sheets with parchment paper.

Shape and roll in sugar. Pour about 1/2 cup of sugar onto a plate. Remove the chilled dough from the fridge and roll into balls, using about 2 tablespoons of dough per cookie. Roll each ball in sugar, coating it well. Place on the cookie sheet, giving each cookie plenty of space to spread. I recommend baking 6 cookies in 2 rows on an 18×13 baking sheet.

Bake. Place in the oven and bake for 12-15 minutes until the edges of the cookies are set and they have crackly tops. The cookies will still be very soft when they are done, this is normal.

Cool. Let the cookies cool for at least 10 minutes. This will give them time to firm up. After the initial cooling time transfer the cookies to a wire rack to finish cooling.