*250g caster sugar
*zest and juice of 2 lemons
*zest and juice of 2 limes
*200ml double cream
*600ml whole milk
*4 large ripe avocados
*pinch of fine sea salt
1. Put the sugar and lemon and lime zest and juice in a heavy-based saucepan.
2. Slowly bring to the boil, stirring to dissolve the sugar. Once the sugar has melted, add the cream and stir well. Gradually bring to the boil. As soon as it starts to bubble up, remove the pan from the heat and pour in the milk.
3. Halve the avocados, then remove the stones, scoop out the flesh and place in a food processor or blender. Pour in the milk and cream mixture and blitz until smooth, scraping the sides to make sure there are no chunks of avocado left.
4. Pour the mixture into the bowl of an ice-cream machine and churn until almost set (or according to the manufacturer’s instructions). Transfer to a clean plastic container and freeze for at least a few hours until firm.
5. If you do not have an ice-cream maker, freeze the mixture in a shallow plastic container. Take it out after a couple of hours and whisk it by hand or with an electric whisk. Repeat the process twice, then return the ice cream to the freezer for a final freeze.
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Carnival! By David Ponte, Lizzy Barber & Jamie Barber (Quadrille £10) Photography: Martin Brigdale