Ingredients

• 275 g all-butter puff pastry (massa folhada)
• 10 g butter
• 200 g granulated sugar
• 120 ml water
• 1 stick cinnamon stick
• 1 lemon peel
• 250 ml whole milk
• 25 g plain flour
• 6 egg yolks
• to taste ground cinnamon
• to taste icing sugar

Method

1. 01
   Heat the oven Turn your oven to its highest setting, ideally between two hundred fifty and two hundred ninety degrees Celsius, with a rack in the upper third, and let it heat fully.
2. 02
   Roll the pastry log Unroll the cold puff pastry sheet and roll it up tightly from the short side into a firm log, then wrap it and chill it in the fridge.
3. 03
   Slice the log Grease a twelve-cup pastel de nata tin or muffin tin with butter, then cut the chilled pastry log into twelve even rounds about two centimetres thick.
4. 04
   Shape the pastry cups Place one round cut side up in each cup, dip your thumb in cold water, and press from the centre outward and up the sides until the pastry is thin and rises just above the rim, then return the tin to the fridge.
5. 05
   Make the sugar syrup Put the sugar, water, cinnamon stick and lemon peel in a small pan and boil, without stirring, until it turns into a clear, slightly thick syrup.
6. 06
   Cook the milk base Whisk the flour into about a quarter of the milk until smooth, bring the rest of the milk to a simmer in another pan, then whisk in the flour mixture and keep whisking over medium heat until it thickens like thin cream.
7. 07
   Combine and cool Pour the hot syrup into the milk in a thin stream while whisking, take out the cinnamon stick and lemon peel, and leave the mixture to cool until just warm.
8. 08
   Add the yolks Whisk the egg yolks into the warm mixture until smooth, then pour it through a sieve into a jug.
9. 09
   Fill the tarts Take the tin from the fridge and pour the custard into each pastry cup until it is about three quarters full.
10. 10
    Bake until blistered Bake the tarts on the upper rack until the pastry is deep golden and crisp and the custard has puffed up with dark scorched spots on top.
11. 11
    Cool and serve Let the tarts rest in the tin until the custard settles, then lift them out and serve warm, dusted with ground cinnamon and a little icing sugar if you like.