The best lemon meringue pie

To make the pastry, combine the flour, icing sugar and butter in a food processor and pulse together until it resembles breadcrumbs. Add the egg yolk and 2-3 tbsp cold water, then pulse again until the dough clumps together. Briefly knead into a ball, shape into a flat disc, then wrap and chill for 30 minutes. To make it by hand, see my tips.

Preheat the oven to 180ºC, gas mark 4. Have a round, 23cm fluted tart tin ready, about 4cm deep. Roll the chilled pastry to a large circle just larger than the tin (about 30cm) and around 0.5cm thick. Gently place into the tin, pushing the dough right into the edges, and prick the bottom with a fork. Roll the rolling pin over the top of the tin to cut off the excess, then chill for 15 minutes.

Fill the pastry with baking parchment and baking beans and bake for 15 minutes. Remove the baking parchment and beans and bake for 10 minutes more, until crisp and golden. Cool while you make the filling.

Put the cornflour and 2 tbsp lemon juice into a medium saucepan. Whisk to a thin, smooth paste, then add the remaining juice and zest. Stir in the sugar and yuzu juice, then add the egg yolks. Gently cook over a low heat for 2-3 minutes, whisking continuously with a small balloon whisk, until the mix slightly thickens and leaves a trail when the whisk is lifted out.

Add the butter and whisk vigorously to combine. Remove from the heat, whisk in the cream, then allow to cool for 10 minutes. Spoon into the pastry case, smooth over with a spatula, then place in the fridge until cold.

For the meringue topping, combine the sugar and 150ml water in a saucepan and stir until the sugar dissolves. Heat on medium for about 5 minutes, or until it reaches 118ºC on a sugar thermometer (soft ball stage). If you don’t have a thermometer, it’s ready when a drop of syrup becomes a soft ball when placed in a bowl of cold water.

Meanwhile, in a mixing bowl or the bowl of a stand mixer, whisk the egg whites until soft peaks form. Slowly pour the hot sugar syrup into the egg whites while whisking on mediumhigh, avoiding the beaters, until all whisked in.

Continue to whisk until the bottom of the bowl feels cool, about 10 minutes. The meringue should be glossy and hold stiff peaks.

Spoon the meringue over the lemon filling and, using a spoon, create a textured mound. Use a cook’s blowtorch (or carefully place under a hot grill) to gently toast the outside of the meringue, then serve immediately.