In a microwave safe bowl, melt the butter till it melts completely. Allow to cool.
In a bowl, take the flour, cocoa powder along with both the sugars, baking soda and mix well.
Next mix the egg replacer with 2 tbsp water and let it sit for a minute.
Then add this mix to the flour and mix well.
Add the melted butter along with the chocolate chunks and combine to form a dough.
If you are not able to form the dough, add a tbsp of milk.
Refrigerate for 10 mins.
Pinch out into balls and flatten it.
Bake in a preheated oven at 185C for 11 to 12 mins.
Check if its done by 10 mins.
Allow to cool down before storing it.