Preheat oven to moderate 180 deg C. Grease and line 20cm x 30cm lamington pan.
Combine flour, coconut and sugar in medium bowl, add melted butter and stir until combined. Press mixture over base of pan. Bake for 15 minutes.

Combine milk, butter and golden syrup in a small heavy base saucepan, stir over heat, without boiling for about 15 minutes until mixture turns golden brown. Pour over hot base and return to oven for a further 10 minutes.

Combine the choc bits and oil in saucepan over medium head, stir continuously with wooden spoon, may need to turn heat down a bit. Stir until smooth and melted and then set aside for a few minutes. Pour over hot caramel and spread and smooth evenly. Stand at room temperature until set. Cut into squares. I store mine in fridge and usually cut it after it has been in the fridge for a little while.