Chocolate Caramel Crispy

1. Grease and line a 20 x 20cm/8" x 8" baking tin with parchment paper.
2. Put the mars bars and butter in a heat proof bowl and place over a pan of barely simmering water. Mixing with a whisk, melt until the mixture is smooth.
3. Pour over the rice krispies in a mixing bowl and mix until all the ingredients are evenly combined. Press evenly into the prepare baking tin and set aside.
4. Melt the milk chocolate in the microwave or over a pan of barely simmering water.
5. Spread the melted chocolate over the rice krispie mixture and leave to set in a cool place. Once set slice into squares and serve!

Cooking notes

Baked goods are unforgiving with rounding — use weights rather than volumes whenever possible, and verify pan capacity if you scale up or down significantly.

For volume-to-weight conversions of any ingredient — flour, sugar, butter, salts — use the ingredient converter. To translate the recipe's oven temperature between °C, °F and gas mark, see the temperature converter.

When you scale this recipe up or down, remember that cooking time does not scale linearly. A doubled cake takes longer, but not twice as long; a doubled soup takes roughly twice as long. The cooking-time guide gives sensible starting estimates by dish geometry.