Preheat the oven to 180°C (356°F).
Melt the dark chocolate and butter together using a double boiler.
Add sugar, salt, and vanilla extract to the melted chocolate mixture and mix well.
Add the eggs and combine thoroughly.
Sift in cake flour and cocoa powder, then fold with a spatula.
Add chocolate chips and mix well.
Scoop the dough into round shapes and place them on a baking pan.
Bake in the oven at 180°C (356°F) for 10-12 minutes.
Let the finished cookies cool.