Rachel Roddy’s recipe for an Italian lemon crumble sandwich dessert
Apparently, when behavioural scientists conduct salivation experiments using lemons, they hide the fruit. The reason for this, according to Margaret Visser in her impeccably researched book Much Depends on Dinner, is that subjects who see a lemon as well as taste one are liable to react in a manner that ruins the saliva measurements. Simply reading this had an enormous effect on my own saliva production, but I also tried to set up an experiment at home. My attempts, however, were sabotaged by family members showing me lemons, which did confirm something we already knew: perfectly packaged, handy in size, readily available, inexpensive, long-lasting and multitalented, lemons bring joy, even before you scratch or squeeze them.
While northern India, with its warm, humid climate that almost never gets colder than 10C, is where lemons very likely originated, Visser also notes that the first clear mention of lemons is, as far as we know, an Arab document from the early 10th century, in which the laimun tree is said to be sensitive to cold. Lemon cultivation in the Mediterranean was certainly the consequence of Arab initiative and the creation of orchards in north Africa, Spain and Sicily; it also seems likely that Arab traders sailed the lemons eastwards to China, where they met the bitter oranges and mandarins that originated in Assam and Myanmar. From China, citrus radiated to Malaysia, which seems to have been a producer of limes and pomelos. The very definition of fruitful encounters and exchange.
But back to our common fruit bowls, which very likely contain one, two or five lemons, and this week’s recipe: a great favourite taught to me by my friend Cinzia Fioravanti just after I moved to Rome in 2005. Like a fruit crumble, this cake/tart takes its name from the action sbriciolata (crumbled), but here the rubbly mixture of flour, sugar and butter is used both as a base and as a topping, which sandwiches a lemon pudding filling. I feel it important to stress that the lemon filling is thickened with eggs and cornstarch, which gives it a homely feel somewhere between blancmange and curd. If this is not to your taste, use lemon curd instead, or indeed a jar of chocolate spread or jam. But if you do like wobbly set puddings this may well be for you.
Because of the nature of the base and topping, it is vital that you let it cool completely before moving it on to a plate. Cinzia inverts hers, so the bottom becomes the top, or simply slides it on to the plate. Grate more lemon zest on top and serve in slices with tea as imagined by Rainer Maria Rilke in a letter to his fiance in 1900: “Great lemons, cut in discs, would sink like suns into the golden dusk of the tea, dimly shining through it with the radiant flesh of their fruit.”
Sbriciolata alla crema al limone – lemon crumble cake-tart
Serves 8-12
300g plain flour
10g baking powder
120g golden caster or demerara sugar
A pinch of salt
120g cold butter, diced
1 large egg, plus 3 egg yolks
3 lemons
500ml whole milk
150g caster sugar
40g cornstarch/cornflour, or plain flour
Working in large bowl, mix the flour, baking powder, sugar and salt. Add the diced butter and the whole egg, then rub in with your fingertips until the mixture resembles fat breadcrumbs. Use half the crumbs to make a loose layer in the base of a buttered shallow 28cm tin and bake 170C (150C fan)/340F/gas 3½ for 10 minutes, until the crumbs are lightly golden. Remove and leave to cool.
Put the milk in a pan and use a grater to take the zest off the lemons, letting it fall directly into the pan. Warm the milk gently over a very low flame, so it infuses.
Meanwhile, in a bowl, whisk the egg yolks with the sugar and cornflour, until they form a thick paste, then whisk in 150ml lemon juice.
Once the milk is simmering, whisk the egg and lemon mixture into it and cook, stirring, until the mixtures thickens like custard. Spread the lemon cream over the crumb base, leaving a 1cm border around the edge, then cover with the remaining crumbs. Bake again for 20 minutes, until the crumbs are golden, then remove and leave to cool completely before inverting on to a plate.
