Ingredients

Sweet Pastry Dough

230g flour, plus a little flour to roll the dough out with

140g softened butter

1 large egg     

1 egg yolk

90g icing sugar

40g ground almonds

4 pinches fleur de sel salt

1 vanilla pod

 

Hazelnut Sponge

115g of raw hazelnuts, roasted and finely ground

95g dark brown sugar

1 egg white (30 g)

2 egg yolks (40 g)

25g icing sugar

2 vanilla pods

105g butter

1 pinch fleur de sel salt

60g cake flour

7g baking powder

4 egg whites (125 g)

20g dark brown sugar

 

Candied Lemon Peel

250 g of lemon juice

150 g of castor sugar

100 g lemon peel

 

Lemon Cream

75g melted butter

120g sugar

3 small eggs

90g lemon juice

1 lemon zest

2g leaf gelatine

 

Italian Meringue

3 egg whites

145g castor sugar

40g water

 

Method

Sweet Pastry Dough

Split the vanilla pod with a knife and scrape out the pulp.

Mash the butter in a large mixing bowl, using a fork to get a texture similar to thick rich cream. Mix in the vanilla pulp and icing sugar. Add the ground almonds, egg and egg yolk, whisking the mixture again. Add half the flour and salt, mix, and then add the other half of the flour and salt to mix evenly, without over mixing into a too-smooth dough.

Set the dough on a floured work surface and flatten it out roughly by pressing on it 3 or 4 times with the palm of your hand.

Wrap it up with plastic wrap, and put it in the refrigerator for at least 3 hours before using it.

Roll out the dough to ½ cm in thickness. Use your rolling pin to pick it up and set it delicately over a lightly buttered baking ring or tart dish, pressing the edges down and into place with your thumbs. Chill in the fridge overnight.

 

Hazelnut Sponge

The next day, combine the powders (ground hazelnuts, 95 g of dark brown sugar, icing sugar and the vanilla pulp scraped out of the split pods) in a large mixing bowl. Add the egg white and 2 egg yolks.

Melt the butter in a small saucepan over medium heat until it browns (toffee coloured), then add it hot to the powder mixture, a third at a time, whisking vigorously after each addition.

Then add the flour, baking powder and salt, and mix everything thoroughly.

Beat the egg whites into soft peaks that just hold together with 20g of the remaining dark brown sugar. Combine the whipped egg whites into the mixture, one half at a time. Be sure not to be too delicate in combining the mixture, in order to achieve a semi-liquid mixture that will fall from the whisk in a ribbon.

Pour the sponge batter directly onto a silicone or greased baking paper sheet set onto a baking sheet. Depending on your oven, bake for 170°C for 6 to 7 minutes.

After baking, wait 5 minutes and delicately remove the sponge from the baking paper. Once cooled, use a round biscuit cutter to cut out circles of sponge slightly smaller than the diameter of the tart.

 

Candied Lemon Peel

Wash the lemons. Using a peeler, remove the lemon zest with as little pith as possible; the pith will make it too bitter.

Put the lemon zests in a little saucepan half full of water and bring to a boil to blanch them. Empty the saucepan contents into a sieve to drain the zests, and blanch them twice more the same way.

The bitterness is mostly in the peel. In blanching the zests three times, the flavour of the candied lemon will come through without the bitterness.

In a larger saucepan, cook these lemon zests with the lemon juice and sugar on a medium heat (simmering), for 40 to 50 minutes. When the mixture has reduced enough, run it hot through a food processor.

Be careful, this mixture will be extremely acid and highly concentrated in flavour.

 

Lemon Cream

Pre-bake the tart shell without letting it brown (lining it with waxed paper and dried beans).

The shell must be completely baked, however, because it will not be going back in the oven.

To make the lemon cream melt the butter in a saucepan; once the butter is melted, add the sugar, eggs, lemon juice and zest. Stir continuously, bringing the mixture almost to a boil. From the first bubble breaking the surface, take the saucepan off the heat and whisk it a little more while adding the leaf gelatine previously soaked in cold water and squeezed in your hand to eliminate the excess water.

Transfer the mixture from the saucepan to another recipient and set aside until the mixture is lukewarm.

When the mixture is between lukewarm and cool, put a teaspoonful at the bottom of the pre-baked tart shell to “glue” the hazelnut sponge into place at the bottom of the shell.  Spread a thin layer of candied lemon over the top of the sponge, then pour the lemon cream on top and spread it out to the edges; smooth it nicely with a spatula and put your tart in the fridge for at least 2 hours or in the freezer for 30 minutes.  This will prepare the surface to receive the meringue.

 

Italian Meringue

Heat the castor sugar with the water in a saucepan until it reaches a temperature of 118°C.

When the syrup reaches 115°C, start to beat the egg whites to peaks, using a food processor on medium speed.

When the egg whites are foamy and form soft peaks (but not too firm), pour the syrup on them (but only when there are no more bubbles in the syrup) in a thin thread while continuing to whip the egg whites at medium speed.

After about 15 minutes, the egg whites will be smooth and shiny, and back down to room temperature; they will form a sharp peak when you pull the whisk out of them.

 

Finishing the meringue

Pour the Italian meringue “in a heap” in the middle of the tart; use a long baker’s spatula to spread it across the entire surface of the tart, bringing the meringue to the edges and to form a slight dome in the middle.

Use a kitchen blowtorch to slightly caramelize the Italian meringue before serving.