Place chopped mars bars into a heatproof bowl with butter and golden syrup.
Microwave for about 1- 1 1/2 minutes or until mars bars are melted.
mix until smooth.
Stir in the rice krispies and press mixture firmly into a greased foil-lined cake tin.
Place in the refridgerator until firm.
Place chocolate pieces into a heatproof bowl.
Microwave for 1-2 minutes or until melted.
stir until smooth.
Spread over slice and refridgerate until firm.
Remove slice from refidgerator about 1 hour before cutting with a warm knife.