Chelsweets' Fudgy Brownie Crinkle Cookies

Preheat the oven to 350°F (175°C) and line two large baking sheets with parchment paper.

Combine the 1 ⅓ cups dark chocolate chips and ¼ cup butter in a heat-proof bowl; melt in 15-second microwave intervals (or over a double boiler) until glossy and smooth, then set aside to cool slightly.

In a separate bowl, vigorously whisk the granulated sugar, room temperature eggs, espresso powder, and salt for 1 minute until pale and aerated (this creates the signature shiny crinkly top).

Whisk the cooled chocolate-butter mixture into the whipped eggs until fully emulsified.

Sift the all-purpose flour, cornstarch, and baking soda directly into the batter; fold with a spatula just until incorporated, then fold in the remaining ⅓ cup chocolate chips.

Let batter rest for 2 to 3 minutes until thickened into a scoopable ribbon consistency.

Use a large cookie scoop to deposit 12 portions (approx. 3 tbsp each) onto the baking sheets, spaced 3 inches apart.

Bake for 12 to 13 minutes, rotating pans halfway through. Sprinkle immediately with flaky sea salt while hot.

Allow cookies to rest on the sheet for 10 minutes to set before transferring to a wire rack.