Martha's salted caramel popcorn squares

1. Grease a 23cm square baking tray with butter. In a large bowl, combine the popcorn, rice pops and pretzels.

2. Place the sugar and 80ml water in a large heavy-based metal saucepan. The mixture will bubble up when the other ingredients are added so make sure you choose a pan that’s large enough. Boil over a medium heat without stirring (this will make the caramel crystallise) until the caramel turns from clear to a light amber colour.

3. Remove the pan from the heat and stir in the double cream. The mixture will bubble vigorously so be really careful when you do this. Add the marshmallows and stir until the mixture is smooth.

4. Working quickly, pour the marshmallow caramel over the
dry ingredients and mix with a wooden spoon, making sure all
the popcorn is covered in the caramel. Tip into the prepared tin and use a small piece of baking parchment to press the sticky mixture right into the edges of the tin. Try to tightly compress the mixture or the squares won’t hold together so well when you cut them.

5. Melt the chocolate in the microwave or over a bain marie, then pour into a piping bag. Drizzle the chocolate over the bars, then top with the remaining pretzels. Chill in the fridge for at least 2 hours so they set firm, before slicing into squares using a sharp knife.