Line and grease a 18 x 32cm slice tray with baking paper and set aside.
Place the butter, sweetened condensed milk and golden syrup in the Thermomix bowl and melt on 60 degrees, Speed 2, 4 minutes.
Add the biscuits and crush on Speed 6, 10 seconds. Add the coconut and licorice allsorts and mix on Reverse, Speed 3, 10 seconds (or until combined - use the spatula to help mix).
Press the mixture into the base of the prepared pan and set aside for 30 minutes to set.
Place the milk chocolate and vegetable oil in a clean and dry Thermomix bowl and melt 50 degrees, Speed 2, 4 minutes.
Pour the melted chocolate over the slice and place into the fridge to set.