Preheat your oven to 350°F.

In a heatproof bowl, melt the butter and chocolate together over a double boiler.

While the chocolate cools, beat the eggs, sugar, and vanilla in a stand mixer fitted with the paddle attachment. Mix on medium for at least 3 minutes. The mixture must look light and airy. The air incorporated by the mixer is what it needs to create the crinkle brownie like tops.

Add in the chocolate and butter mixture and mix until combined.

Add flour, salt, cocoa powder and baking soda. Mix until combined on low. The dough will be loose and look more like brownie batter than cookie dough.

Using a mini ice cream scoop or a small spoon, spoon the cookie dough onto a parchment lined baking sheet or sheet tray leaving 2 inches in between the cookies to allow them to spread.

Bake the cookies for 10 minutes.

Notes :
If the cookies don't come out with the crinkle tops it's because the eggs were either too cold or not whipped well enough.