Nothing says Portugal quite like a Portuguese custard tart — wobbly egg custard encased in layers of buttery pastry — which manages to be both crunchy and soft at the same time.
A tip: avoid using a non-stick tart tin, as the high temperatures may break down the non-stick coating, which isn’t good for it or for you.
Makes: 24 tarts
Takes: 2.5 hrs, plus minimum 3 hrs chilling time
For the pastry
275g plain flour, plus more to dust
¼ tsp fine salt
200g unsalted butter, beaten until soft
For the custard filling
250g caster sugar
600ml whole milk
1 vanilla pod, split lengthways
½ cinnamon stick
pared rind of ½ unwaxed lemon, cut into long strips
12 egg yolks
icing sugar, to serve
ground cinnamon, to serve
1 In a bowl, using a spoon and then your hands, mix together the flour, salt and as much cold water (roughly 125ml-175ml) as necessary to make a soft, light dough. As soon as it starts to come together, turn it out onto a floured work surface. Press then roll it out with a rolling pin to form a 15cm square. Wrap the pastry in cling film and chill in the fridge for 20 mins.
2 Roll out the chilled pastry to form a rough 45cm square, using lots of flour to prevent it sticking to the surface or the rolling pin. Trim the edges to neaten it up. Divide the beaten butter into three roughly equal quantities. If it’s looking glossy or beginning to melt, pause here and chill it and the pastry for 10 mins. Use a palette knife or spatula to spread one third of the butter over the left-hand two-thirds of the pastry, leaving a 3cm gap around the edges.
3 Working quickly, fold the unbuttered right-hand third over the buttered middle third. (Use a pastry scraper or palette knife to loosen the dough, if necessary.) Working from the top down, pat the pastry to remove any air bubbles. Touch the pastry as little as possible, to stop it getting too warm.
4 Next, fold the buttered left-hand third over too, so that it covers newly visible unbuttered pastry. You should now have a long rectangle of pastry and no visible butter. Pat briefly to remove any bubbles. At this stage, the butter within the pastry layers can become a bit soft, especially on a hot day. If this happens, chill the dough for 10 mins to allow the butter to firm up.
5 Turn the pastry rectangle so one of the long sides is facing you. Gently roll it out with the rolling pin to form a square again, being careful not to burst the layers of butter when you reach the edges of the pastry.
6 Repeat the spreading-folding process with the second third of the butter, using lots of flour on the work surface and rolling pin again. Chill again if necessary.
7 Roll out the pastry for a third time, into a rectangle roughly 45cm × 55cm, using lots of flour under the pastry and on the rolling pin. Working quickly, spread the remaining butter all over the pastry, leaving a 3cm gap around the edge. Spread it as thinly as you can, but be gentle, as the pastry will be fragile and prone to tearing.
8 Starting with a shorter edge, roll the pastry into a tight log shape, brushing off excess flour as you go. Trim the ends so that the edges are even, cut the log in half, wrap the two halves in cling film and chill in the fridge for at least 3 hrs or overnight. (You can freeze the pastry at this stage. Defrost overnight in the fridge before using.)
9 To make the custard, place the sugar and water in a saucepan and heat until the mixture reaches 105C on a pan thermometer. Remove from the heat and set aside. In a separate pan, heat the milk until just below boiling point, then add the vanilla pod, cinnamon stick and lemon rind. Remove from the heat and leave to infuse for 5 mins or so.
10 Whisk the egg yolks in a large, heavy bowl until smooth and creamy. Remove the vanilla pod, cinnamon and lemon rind from the milk. Skim off any skin that’s formed. Add a tablespoon of the hot milk to the egg yolks and whisk vigorously. Continue adding the hot milk, a tablespoon at a time, adding it slowly but whisking quickly, so the eggs don’t scramble.
11 After adding 6–7 tablespoons of milk, slowly pour the remaining hot milk into the bowl, continually beating the mixture. Finally, add the sugar syrup in a steady stream, whisking continuously.
12 Quickly wash the milk pan, then tip the custard mixture back into it. Set the pan over the lowest possible heat and cook the custard very, very gently, stirring continuously and running a spatula around the bottom and edges of the pan every now and then, to make sure all the liquid is moving all the time.
13 After 8–25 mins of gentle cooking, depending on your pan, the mixture should begin to thicken. If you have a pan thermometer, thickening will occur at about 75C. Don’t let it get hotter than 80C as the custard may split. As soon as the custard has thickened to the consistency of double cream, remove it from the heat and pour into a clean, heatproof bowl. Cover the surface with cling film to prevent a skin forming, and set aside.
14 An hour before you want to cook the tarts, preheat your oven to its maximum temperature, ideally 275C, 255 fan, gas 10. If you have a pizza stone, place it on the top shelf of the oven, or use a baking tray. Place a second pizza stone, or another baking tray, on the middle shelf of the oven. Let them both get really hot. This is the best way to replicate the fierce heat of bakery ovens, and will allow the tarts to cook quickly with crispy bases and (hopefully) to caramelise on top. Leave just enough space between the stones or trays for the tarts.
15 Next, grease the holes of a shallow 12-hole tart tin and have a cup of cold water ready. Remove one of the pastry logs from the fridge and leave it for about 10 mins until it becomes pliable. Slice it into 12 discs and place each one into the tin (for the end slices, make sure they’re cut side down).
16 Dip your thumbs into the cold water and gently press the dough downwards and outwards, pushing it into the edges of the tin so that, ultimately, it fans out about 1cm above the edge of the tin. Try not to pinch these protruding edges though — if you can leave them a little thicker, they’ll frill out during cooking. The pastry will be about 2mm thick at this point. Press the pastry edges slightly outwards, so they don’t collapse inwards as they cook. They should be in the shape of an upturned hat with a brim.
17 Pour the custard into each tart case, filling them generously and leaving about 7.5mm of the pastry rim showing. Carefully slide the tray into the very hot oven. Bake the tarts for 10–16 mins, possibly slightly longer if your oven can’t reach very high temperatures, checking them every few mins after the first 10 mins. The pastry edges may shrink down slightly and may appear to burn a little, but hold your nerve: slightly burnt bitterness is part of their characteristic flavour, and if you remove them from the oven too soon, the custard won’t caramelise on top. (Caramelising the custard remains a bit of a dark art — sometimes it happens and sometimes it doesn’t. You can use a blowtorch if you really want, but your pasteis de nata will look more like crème brûlées.)
18 When ready, the tart pastry will be brown and occasionally even slightly charred, with a few brown spots on top of the custard. Remove and leave the tarts to cool in the tin. (Don’t worry if a little butter seems to have escaped from the pastry – as they cool, this will resolve itself.)
19 Clean the tin and repeat with the second half of the pastry, if using. Eat warm, dusted with a little icing sugar and ground cinnamon.
Excerpted from Lisbon: Recipes from the Heart of Portugal by Rebecca Seal (£25, Hardie Grant)