Sift flour, cocoa powder, baking powder and salt together, than pour into a large bowl and set aside.
Whisk together eggs and sugar in another bowl.
Add in milk, melted butter and vanilla and whisk until smooth.
Pour the wet ingredients over the dry ingredients. Fold in until just combined.
Spray Ebelskiver pan with cooking spray and place over medium heat.
Pour or scoop batter into each well almost to the top.
Cook for about 2 minutes.
Use 2 long skewers and place on each side of the ebelskiver and turn it over. Let the wet batter flow into the well.
Cook for another 2 minutes.
Move to a platter and enjoy!