Use a stick blender to blend the cottage with and milk together until smooth.
Add the eggs and the brown sugar to the blended cottage cheese mixture and which until sugar has dissolved.
Combine, in a large bowl, the flour, cocoa powder, salt, and baking powder. Use a whisk to mix the dry ingredients.
Pour the cottage cheese mixture into the bowl of dry ingredients. Use a rubber spatula to start mixing the batter.
Pour the melted butter into the waffle batter and fold it in until full incorporated.
Spray the inside of the waffle iron with non-stick spray once the iron is at temperature. Follow your waffle iron's instructions for the amount of batter it suggests. When making an 8-inch waffle, it takes 1 cup of batter.