Preheat the oven to 400°F (200°C).

Roll out the puff pastry to fit a tart pan or a pie dish.

Press the pastry into the pan and trim excess edges. Prick the base with a fork.

2. Make the Custard

In a saucepan, heat milk over medium heat until warm.

In a separate bowl, whisk egg yolks, sugar, and cornstarch until smooth.

Slowly pour warm milk into the yolk mixture while whisking continuously to prevent curdling.

Return the mixture to the saucepan and cook on low heat until it thickens slightly.

Stir in vanilla, cinnamon, and lemon zest (if using).

3. Assemble the Tart

Pour the custard into the prepared puff pastry shell.

Smooth the top and sprinkle lightly with cinnamon.

4. Bake

Bake in the preheated oven for 25–30 minutes, or until the custard is set and the top is caramelized.

Watch carefully near the end to avoid over-browning.

5. Cool and Serve

Let the tart cool slightly before slicing.

Serve warm or at room temperature. Optional: sprinkle with a little powdered sugar or extra cinnamon.

Serving and Storage Tips