To begin, preheat your oven to 250°C or its highest setting. Place a rack in the upper third of the oven. High heat is essential for achieving the signature caramelised tops. Move to preparing the sugar syrup.

In a small saucepan, combine the sugar, water, cinnamon stick, and lemon peel. Bring to a boil without stirring. Let it bubble for about 3 minutes until slightly thickened. Remove from heat and allow it to infuse while cooling slightly.

In another saucepan, whisk the flour with a splash of milk to form a smooth paste. Slowly add the remaining milk and whisk until smooth. Heat over medium, stirring constantly, until the mixture thickens slightly. Remove from heat.

Remove the cinnamon stick and lemon peel from the syrup. Slowly whisk the warm syrup into the milk mixture. Let it cool to lukewarm before adding egg yolks. Proceed to enrich with eggs.

Whisk the egg yolks into the cooled mixture until smooth and well combined. Strain through a fine sieve to ensure a silky texture. Set aside the custard while you prepare the tart shells.

Unroll the puff pastry and roll it tightly into a log. Cut into 12 even rounds. Press each round into a greased muffin tin cup, using your thumb to push and stretch the dough to the top edge. Move to filling.

Fill each pastry shell about three quarters full with the custard. Do not overfill, as the custard will puff slightly during baking. Prepare to bake immediately.

Place the tray in the hot oven and bake for 12–15 minutes, or until the tops are blistered and golden brown. Watch closely near the end to prevent burning. Remove and cool slightly before serving.

Serve Pastéis de Nata warm, dusted with ground cinnamon or icing sugar if desired. Presentation tip: Pair with a bica (Portuguese espresso) for an authentic café style experience.