Preheat your oven to 350°F (175°C) and line a large baking sheet with parchment paper.

In a medium saucepan over low heat, melt the unsalted butter and chopped dark chocolate together until smooth.

In a separate bowl, whisk together all-purpose flour, Dutch process cocoa powder, salt, and baking powder.

In a large mixing bowl, beat together granulated sugar, light brown sugar, eggs, and vanilla extract until light and frothy.

Fold the cooled chocolate and butter mixture into the sugar and egg mixture until just combined.

Gradually add the dry mixture to the wet mixture, mixing gently until combined.

Using a scoop, drop heaping portions of dough onto the prepared baking sheet.

Bake in the preheated oven for 11-12 minutes until the tops crack slightly.

Cool on the baking sheet for 5 minutes before transferring to a wire rack.

Sprinkle with flaky sea salt before serving.