Mix almond flour and cocoa powder in a bowl.
Add erythritol, baking powder, and salt, and mix well.
Add eggs, milk, and melted coconut oil to make the dough.
Fold in chopped dark chocolate.
Shape the dough into rounds and place them on a baking pan lined with parchment paper.
Bake in a preheated oven at 180°C (356°F) for 15–18 minutes.