Start by gently heating the butter and sugars in a sauce pan. Once the butter has melted, take it off heat and stor in the flour, cocoa, baking powder and egg to form a smooth batter.
Now, line and dust a 8 inch square cake tin making sure to leave some paper overhanging at the side. Pour the batter into the pan. Now push the milk chocolate into the batter at regular intervals.
Preheat the oven to 180C and bake for 35-40 minutes. Cool for 10 minutes and then lift out and cool completely. Next proceed to make the fudge while the brownies are cooling. If desired, you can omit the fudge and have it as is. Just drizzle some chocolate syrup over it and a sprinkling of sea salt.
For the Nutella fudge
Put all the ingredients in a glass bowl and melt over another bowl of gently simmering water. Be sure not to let the glass bowl touch the water. Stor for 5-6 mins till the chocolate chip has melted and everything is smooth.
Now, pour this over the brownies if desired. Cut into 16 squares once the fudge has set. Keep it covered in an air tight container for 3 days or freeze of 2 months.