Martha Collison whips the egg whites with hot syrup in this recipe to achieve a light texture that’s marshmallow-like and holds perfectly on top of the tart lemon filling, while lightly toasting with a blowtorch adds the complexity you need. Yuzu is the secret ingredient for a citrus filling that’s mouth-puckeringly sharp.
- Prepare45 mins
- Cook30 mins
- Total time1 hr 15 mins
- PlusPreparation time 45 minutes + chilling
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.
The best pastry
If you’ve got a food processor, pastry is the best thing you can use it for. Warm fingers can melt butter prematurely, whereas the cold blade of a food processor does the job quickly and effectively, avoiding tough pastry. However, to make by hand, rub the flour, sugar and butter together into crumbs using your fingertips. Mix in the yolk with a roundbladed knife until the dough clumps together. Briefly knead, shape and chill as in step 1.
Add some zing
Yuzu is a small, yellow citrus fruit, often used in Japanese and Chinese cuisine. It has the flavour of sharp mandarin, with a hint of lime and the acidity of a lemon. It’s my secret weapon for boosting citrus flavour and adding a sherbet-like tang. If you can’t get hold of it, try using lime juice instead.
Make it ahead
After topping the pie with meringue, aim to serve within about 2 hours – the sugar syrup may start to gather between the filling and meringue if left for longer. You can make all the component parts up to 2 days ahead and assemble on the day. Store the meringue in the fridge in a large piping bag or airtight container and give it a quick whisk to loosen before topping.