I think I've been doing it wrong for years.
I melt marshmallows to mix with the rice crispies, flatten into tin then top with melted mars bars mixed with a little milk, leave to set.
I always thought the marshmallow bit was a pita, really sticky and difficult to flatten down without it all sticking to anything with a metre radius and then recently I have heard that I'm supposed to just mix the melted mars bars with the crispies and poor melted chocolate on top.
Which method do you use, fancy making some this weekend.