Brown 1/2 cup butter, then add cubed butter and melt together. Let cool.

Mix melted butters with dark brown sugar, white sugar, egg, egg yolk, and vanilla.

Add all-purpose flour, cake flour, and baking soda. Mix until just combined.

Fold in rough chopped chocolate and chocolate chips.

Chill dough for 1 hour.

Scoop onto baking sheet.

Bake at 180°C (350°F) for 10-12 minutes.

Sprinkle sea salt on cookies right after baking.