Place a saucepan with about 2cm of water over and medium heat. Chop the chocolate into small pieces.

Place the chocolate into a heatproof bowl and sit the bowl over the pot without it touching the water. Allow the chocolate to melt slowly, making sure none of the steam escapes up the sides and into the chocolate as this will cause it to go grainy. You may want to reduce the heat to low once the water begins to simmer.

Place the rice krispies in a bowl, and when the chocolate is melted, pour it in and mix until combined.

Press the mixture into the base and sides of a 23cm (9in) round cake tin with a removable base. Place in the freezer to firm up for about 10 minutes.

Take the ice cream out of the freezer and allow it to soften slightly at room temperature so that it’s easy to spread. Scoop the ice cream into a bowl and gently fold through the caramel until you have nice swirls. Try not to overmix as you want to see the swirls distinctly when you cut through the cake.

Spread the ice cream on the rice krispie base and place in the freezer, covered in foil, for about 2 hours until set.

Remove from the freezer about 8 minutes before you plan to serve.