- To make a sauce. Combine water, hazelnut spread and brown sugar into a small saucepan, stir and bring to the boil, remove from heat.
- Into a bowl add flour, caster sugar, cocoa, baking powder and mix and set aside. Into a small saucepan over a low heat add butter and allow to melt, add milk and stir.
- Pour the butter mixture into the bowl of dry ingredients, add egg and mix together until combined. Pour batter into a greased oven-proof dish, pour chocolate sauce over the batter. Place into the oven and bake for 40 minutes.
- Serve with ice cream.