Preheat Oven 180C
Line a 10 X 20 cm loaf tin with baking paper.
Whisk the condensed milk, flour, golden syrup, egg, vanilla and milk together until combined.
Place a third of the biscuits on the base of loaf tin, breaking biscuits to fit if needed.
Pour one third of the condensed milk mixture over the biscuits and sprinkle with one third of the chocolate.
Repeat with the remaining ingredients to end with 3 layers in total, finishing with chocolate.
Gently press the top layer to absorb some of the condensed milk mixture.
Bake for 35-40 minutes then set aside for 20-30 minutes.
Using the baking paper, carefully lift the pudding out of the pan and place on a serving platter (the centre will still be a little gooey)
Serve slices of the pudding with thick cream.