Ingredients:
For the Pastry:
1 sheet frozen puff pastry, thawed
Flour, for dusting

For the Custard Filling:
1 cup whole milk
1/2 cup heavy cream
1/2 cup granulated sugar
1 cinnamon stick
1 strip of lemon peel
2 tablespoons all-purpose flour
2 tablespoons cornstarch
4 large egg yolks
1 teaspoon vanilla extract

For Dusting (optional):
Powdered sugar
Ground cinnamon

Instructions:
Preheat your oven to 400°F (200°C). Grease a 12-cup muffin tin or tart molds.
On a lightly floured surface, roll out the puff pastry to about 1/8 inch thickness. Using a round cutter or glass, cut out circles of pastry slightly larger than the diameter of your muffin cups.
Press the pastry circles into the prepared muffin cups, ensuring they cover the bottom and sides evenly. Prick the bottoms of the pastry with a fork to prevent them from puffing up too much during baking. Place the muffin tin in the refrigerator while you prepare the custard filling.
In a saucepan, combine the whole milk, heavy cream, granulated sugar, cinnamon stick, and lemon peel. Heat over medium heat until it just begins to simmer, then remove from heat and let it steep for 10-15 minutes to infuse the flavors.
In a separate bowl, whisk together the flour, cornstarch, egg yolks, and vanilla extract until smooth.
Remove the cinnamon stick and lemon peel from the milk mixture, then gradually whisk the milk mixture into the egg yolk mixture until well combined.
Return the custard mixture to the saucepan and cook over medium heat, stirring constantly, until thickened and smooth, about 5-7 minutes. Be careful not to let the mixture boil.
Once the custard is thickened, remove it from the heat and let it cool slightly.
Remove the muffin tin from the refrigerator and fill each pastry cup with the custard filling, about 3/4 full.
Bake in the preheated oven for 15-20 minutes, or until the pastry is golden brown and the custard is set with a slight jiggle in the center.
Remove the Pastel de Nata from the oven and let them cool in the muffin tin for a few minutes before transferring them to a wire rack to cool completely.
Once cooled, dust the Pastel de Nata with powdered sugar and ground cinnamon, if desired.
Serve and enjoy the deliciousness of these homemade Portuguese custard tarts with a cup of coffee or tea!