Pour water into a small pot ¼ full. Place heat proof plate over the pan. Brake chocolate bar to small pieces and add it into a plate and then pour milk.
Place the pot with water and plate over it onto a stove top and turn it on high and bring the water in the pot to a boil. Reduce the heat to low and start mixing the milk with chocolate constantly until it becomes smooth in texture with no lumps. Remove the plate carefully from the pot and set aside for the ganache to cool.
Once the ganache is cool add 2 tbsp. more of cold milk and then mix well again. You can add more milk or less it depends what thickness you need for your topping decoration.