The Boy Who Bakes

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French Lemon Tarts

What does it take for a brit to get his hands on some meyer lemons? Turns out it’s a simple matter of one transatlantic flight, a garden in Alabama, and an editor willing to carry some in his hand luggage on another flight across America! Simple really. On a trip to NYC, at the end of last year, I was determined to get my hands on some meyer lemons, the less sour, sweeter and more perfumed cousin to the classic lemon we all know and love. Maybe its because living in the cold winter tundra of London the idea of those lemons, grown in warmer environs, warms my heart or maybe its simply I like the idea of using something I cant normally get my hands on, either way I was excited to see what all the fuss is about. Enter my editors at Bake From Scratch, Brian and Brooke, who conspired to get a bag of lemons to me, grown in a garden in Alabama and hand delivered to me in NYC, if thats not friendship I'm not sure what is. Edit: I should say Brian didn't fly to NYC just to deliver me some lemons, that would be crazy, he was already coming to town!

I was determined to use them in something where the lemon flavour would shine and not be beaten into submission by sugar, or overpowered by countless other ingredients. A lemon tart seemed the perfect test subject. Now, while there is absolutely nothing wrong with a classic baked lemon tart my preference is the french lemon cream tart (me make a french dish, how unsurprising!). The texture of the cream is a silky, buttery dream but starts off in the same way as any traditional lemon curd. You cook the lemon together with sugar and eggs until thickened, then off the heat add the butter. So far so familiar, but it’s the exact method that makes this all so special. Firstly the amount of butter is increased, isn't everything better when there is more butter, and secondly it’s the way it is incorporated into the curd that makes the world of difference. With a traditional curd you either cook the butter and lemon mixture together, which in my mind is the worst method, or it is added immediately after the egg mixture is cooked. Both of these methods melt the butter fully, giving a greasier fattier end product. By waiting for the egg mixture to cool slightly and then slowly emulsifying the butter in a bit by bit you end up with something that is somewhere between a traditional curd and a french buttercream made with egg yolks, beautifully silky and the perfect tart filling. 

I cannot say with any accuracy or confidence who invented this style of cream but the first place I encountered it was in the pages of one of the Pierre Herme books written by the wonderful Dorie Greenspan, and it is her basic method I have used ever since (although the ratio of ingredients in my version is different to suit my tastes). Over the years this style has become incredibly popular and if you visit the patisseries of Paris these days your lemon tart is more likely to be made with this method than the traditional baked method. If you want a different version you can use any citrus to make the cream, adjusting the sugar to fit the sharpness of the fruit. As I was using meyer lemons I knocked the sugar down just a tad, but the recipe below is for regular lemons.

Lemon Cream Tarts
Makes 6

Lemon Cream
150ml lemon juice
zest of 3 lemons
2 large eggs
2 large egg yolks
150g caster sugar
225g unsalted butter, diced and at room temperature

Pate Sucree
recipe here

Start with the lemon cream as it needs ample chilling time before it is ready to use. Add the lemon juice, lemon zest, eggs, egg yolks and caster sugar into a heatproof bowl set over a pan of simmering water and cook, stirring regularly until the mixture reaches 80c on an instant read thermometer. The temperature is key because it needs to be fully cooked like a custard so the finished cream holds the correct texture. I have said here to do this stage in a bain marie but half of the time I just place the ingredients directly into a saucepan and do this over a low heat stirring constantly. It is quicker than the bain marie method but it is also more prone to catching and overcooking so if you decide to do it this way be very careful and keep the heat down low. 

Once the custard is cooked pour it into a large jug, through a fine sieve to remove any cooked egg bits, allowing to cool for 15 minutes, when it should be about 60c. Using some form of blender (traditional jug style or stick blender both work great) blend in the butter a couple piece at a time. If using a stick blender do this in the jug you cooled the curd, the depth of the jug means you wont end up incorporating too much air which you're trying to avoid (the same reason it is best not to use a food processor). Once all of the butter has been incorporated pour the cream into a container, press a sheet of clingfilm onto the surface of the custard and refrigerate for at least fours hours, until the mixture thickens up. 

Remove the chilled pastry from the fridge and cut into six equal sized pieces and working with one at a time roll out, on a lightly floured worksurface, until 2-3mm thick. Use to line either six 10cm loose bottomed tart tins or as I do use tart rings, which give a more modern style. Trim off the excess and set onto a parchment lined baking tray. Line each tart with a piece of crumpled parchment paper and fill with rice (I prefer rice to baking beans as they are lighter and smaller so less likely to damage the delicate pastry but mainly they are smaller so fit into the corners of the pastry better so you get a better finish, plus rice is much cheaper). 

Blind bake the tart shells at 190c for about 15/20 minutes before removing the rice and parchment  and baking for a further 10 minutes or until the inside is nice and golden. Once baked set aside to cool. Once ready to serve remove the cream from the fridge and fill the tart shells. Set back in the fridge for about 30 minutes before serving to firm up again. For this version I have topped with a little bit of swiss meringue, blowtorching to give a lemon meringue tart vibe. 

The cream can be made a few days in advance but once the tart shells are filled with the cream they are best eaten the same day.