Step 1

To make the pastry, process the flour, butter and icing sugar in a food processor until the mixture resembles fine breadcrumbs. Add the egg yolk and water. Process until the dough just comes together. Turn onto a lightly floured surface. Knead until just smooth. Shape into a disc. Cover with plastic wrap. Place in the fridge for 30 minutes to rest.

Step 2

Turn the pastry onto a lightly floured surface. Use a lightly floured rolling pin to roll the pastry out to a 3mm-thick disc. Line a round 28cm (base measurement) fluted tart tin, with removable base, with the pastry. Trim any excess. Place in the freezer for 1 hour to rest.

Step 3

Preheat oven to 200C. Line the pastry case with baking paper. Fill with pastry weights or rice. Bake for 15 minutes. Remove paper and pastry weights or rice. Bake for 8 minutes or until light golden.

Step 4

Meanwhile, bring the cream and coconut milk to a gentle simmer in a saucepan over medium heat (do not boil). Whisk the egg yolks and caster sugar in a heatproof bowl until well combined. Whisk the hot cream mixture into the egg yolk mixture. Strain through a fine sieve into a jug. Stir in the lime rind.

Step 5

Reduce oven to 150C. Pour custard mixture into pastry case. Bake for 35 minutes or until just set. Place in the fridge for 2 hours to cool. Sprinkle over the raw caster sugar. Shake the tart gently to evenly coat. Use a blowtorch to caramelise.