01 -
Position the oven rack just above center and preheat oven to 350°F. Line two baking sheets with parchment paper or silicone mats and set aside.
02 -
In a medium mixing bowl, whisk together all-purpose flour, baking powder, salt, cocoa powder, and espresso powder until evenly incorporated. Set aside.
03 -
In a separate large mixing bowl, use a hand mixer or stand mixer with the paddle attachment to beat eggs, egg yolk, granulated sugar, vegetable oil, and vanilla extract on medium-high speed until fully combined and frothy.
04 -
In a small saucepan over medium heat, melt the semi-sweet chocolate chips and unsalted butter together, stirring until smooth. Remove from heat and immediately whisk in the cocoa powder and espresso powder.
05 -
Pour the melted chocolate mixture into the wet ingredients and mix on medium speed until uniformly combined.
06 -
Gradually add the dry ingredients to the wet mixture and beat on low speed just until a cohesive batter forms.
07 -
Scoop tablespoon-sized portions of dough onto the prepared baking sheets, spacing them at least 2 inches apart. Gently press a few extra chocolate chips on top of each dough mound if desired.
08 -
Sprinkle a pinch of sea salt flakes over each cookie. Bake for 8-10 minutes at 350°F, or until the tops are shiny and crackled but centers remain soft.
09 -
Allow cookies to rest on the baking sheets for 5 minutes before transferring carefully to a cooling rack. Serve warm or let cool completely.