Method:

For the pastry: in the large bowl of an electric mixer, cream together the butter and icing sugar using the paddle attachment until well combined and smooth.

Gradually add the eggs and beat until the mixture becomes light and airy - but not too fluffy.

Sift in the flour, ground almonds and salt. Knead by hand to form a smooth dough. Shape into a ball, flatten into a disc, cover with cling film and chill for 30 minutes.

Preheat the oven to 160°C Fan. 

Lightly dust a work surface and rolling pin with flour and roll out the pastry to a large circle, about ½ cm thick and about 10 cm larger on each side than your tart tin 

Use to line a 25cm (10-inch) loose-based tart tin. Prick the base with a fork.  

Bake for 10-15 minutes until golden brown and just sandy to touch. Allow to cool completely.

Meanwhile, make the lemon curd: in a heat-proof bowl, mix together the lemon juice and zest, butter, eggs and sugar. Place over a pan of very gently simmering water, stirring constantly until the mixture thickens and coats the back of a spoon. Remove from heat and strain through a fine sieve to remove any lumps.

Soften the gelatine in cold water for 2 minutes or until it’s completely soft. Remove from the water, squeeze out any excess liquid, then add to the warm lemon curd, stirring until completely dissolved. Leave the curd to cool for about 10 minutes.

Pour the curd into the baked tart shell in a smooth and even layer. Leave to cool completely before chilling for 1 hour, or until set.

Once the curd has set, prepare the Italian meringue: in a small saucepan, combine the sugar and water. Place over a medium heat until the sugar dissolves and the syrup reaches 118°C on a sugar thermometer.

Meanwhile, in a clean, dry bowl, begin whisking the egg whites until they form soft peaks.

Once the sugar syrup has reached the correct temperature, slowly pour it into the egg whites while continuing to whisk - take care to pour the syrup down the side of the bowl (not onto the whisks) to avoid splattering.

Continue to whisk the egg whites until the meringue is glossy and forms stiff peaks, and the bowl has cooled to room temperature.

To assemble: remove the tart from the tin and set onto a flat plate. Spread or pipe the Italian meringue over the set lemon curd. Use a blowtorch to lightly brown the meringue, or place under a grill for a few seconds - watch closely to prevent burning.

Serve chilled or at room temperature decorated with lemon zest, if wished