Preheat your oven to 350°F and position racks in the upper and lower thirds so you can bake two sheets simultaneously if needed. While the oven heats, prepare two shallow bowls: fill one with granulated sugar and the other with powdered sugar. This setup ensures you can quickly coat the dough balls without fumbling around mid-rolling. Set out your baking sheets and line them with parchment paper if desired—these cookies spread minimally, so lining is optional but helpful for easy cleanup.

In a large mixing bowl, combine the softened unsalted butter with the brown sugar and the 1/3 cup granulated sugar. Beat on medium-high speed for about 2 minutes until the mixture is light, fluffy, and noticeably paler in color. This creaming process incorporates air into the dough, which helps the cookies achieve their signature crinkly texture. I find that slightly underbeating is better than overbeating here—you want fluffy, not dense.

Add the two large eggs to the creamed butter mixture along with the vanilla extract and peppermint extract. Beat on medium speed for about 1 minute until the mixture is smooth and fully combined. The eggs emulsify with the butter, creating a smooth, glossy batter. The peppermint extract should distribute evenly at this stage—if you add it later with the dry ingredients, you risk uneven flavor distribution throughout the cookies.

Sift together the all-purpose flour, Dutch processed cocoa powder, baking powder, baking soda, and salt in a separate bowl to break up any lumps and distribute the leavening agents evenly. Add this dry mixture to the wet ingredients and fold or stir gently with a spatula until just combined—about 30 seconds. Overmixing at this stage develops gluten, which would make the cookies tough rather than tender. The dough should look slightly shaggy but hold together when squeezed. I like using Dutch processed cocoa here because it's been alkalized, giving a deeper, more refined chocolate flavor compared to natural cocoa.

Using a 1-tablespoon cookie scoop or your hands, form the dough from Step 4 into balls about the size of walnuts. Working with one ball at a time, roll it first in the granulated sugar until lightly coated, then immediately roll it in the powdered sugar for the signature crinkle effect. The granulated sugar adds a slight grit and texture, while the powdered sugar creates that beautiful crackled appearance as the cookies bake and spread. If the dough becomes warm or sticky while working, refrigerate it for 10 minutes to make handling easier.

Arrange the coated dough balls on your prepared baking sheets, spacing them about 2 inches apart. Bake for 9 to 10 minutes at 350°F—the cookies will look slightly underdone in the center, but they'll firm up as they cool. The tops will be cracked and visibly darker at the edges. Remove from the oven and let the cookies rest on the baking sheet for 2 minutes before transferring them to a wire rack to cool completely. This resting period prevents breakage and allows carryover cooking to finish setting the centers.