Here's the recipe for the crispie - this makes 1 rectangular baking tin (swiss roll) full, and cuts into about 30 pieces.
1x250g block of butter (I prefer slightly salted)
1x200g bag of marshmallows (mini or regular, pink or white!)
1x150g toffees (e.g. McCowans or Werthers)
Rice Crispies - quite a lot - a good 200g, but it depends on how sticky you want your crispie.
Put the butter and toffee in a pan over very low heat and leave to melt, stirring occasionally. At the same time, line your tin with grease proof paper - it will make cutting and removing from the tin a LOT easier!
Once the toffee and butter have melted, tip in the marshmallows and stir continuously until melted and smooth. It will go separated for a while and then suddenly all comes together.
Add the crispies and stir in quickly until well coated - add more or less depending on the required consistency.