Set your oven to 350°F and prepare two baking sheets with parchment paper.
Combine the butter and semi sweet chocolate in a microwave-safe bowl and heat in 30-second bursts until fully melted, then let it cool slightly.
In a separate large bowl, use a mixer fitted with a whisk attachment to beat the eggs, sugar, and vanilla extract on high speed for 3 to 5 minutes until the mixture turns light and fluffy.
Slowly mix in the cooled chocolate and butter blend until everything is evenly incorporated.
Add the flour, kosher salt, cocoa powder, and baking soda, then fold them in gently just until combined – the batter should resemble a loose brownie batter rather than typical cookie dough.
Drop spoonfuls of the dough onto the prepared pans, spacing them about 2 inches apart to allow for spreading.
Bake the cookies for 10 minutes until they develop a crinkly surface and the edges appear set and slightly crisp.
Allow the cookies to cool on the baking sheets for 10 minutes before moving them to a wire rack to cool completely.
