First, make the ice cream - whisk together condensed milk, peanut butter and vanilla essence.
In a separate bowl whisk the cream until it forms stiff peaks then fold in the peanut butter/condensed milk mixture, being careful to not knock too much air from the mix.
When you've got a smooth mix resembling melted ice cream pour it into a lined brownie tray and freeze until solid.
Preheat oven to 180°C/350°F.
Pour hot melted butter over the chocolate in a pyrex bowl and stir until the mixture is completely smooth. You can also add room temperature butter and chocolate to a bowl and microwave in 30 second bursts until smooth, or do it over a bain marie - the choice is yours.
Whisk the eggs and sugars together until the mixture is thoroughly mixed, smooth and light.
Add the (cooled) chocolate/butter mix to the eggs and sugar and stir to make a glossy batter.
Use a sieve to sift in the flours and cocoa powder.
Divide into two lined brownie tins and bake for 17 mins until risen with a nice shiny skin. Leave to cool completely before sandwiching the ice cream centre and cutting into 9 equal squares.
Place them on a rack above a baking tray and pour the chocolate over them. Eat, quickly!