1. Make the crust:
Preheat oven to 180°C.
In a bowl, mix flour, baking powder, and salt. Rub in butter until crumbly. Add sugar, egg, and vanilla and mix to form a soft dough.

Press the dough into a greased tart dish or pie tin (about 23–25cm). Prick the base with a fork and bake for 10–12 minutes until lightly golden. Set aside to cool slightly.

2. Make the filling:
In a pot, heat milk with the cinnamon stick until just before boiling. Remove from heat and let it infuse for 5–10 minutes. Remove cinnamon stick.

In a bowl, whisk eggs, sugar, flour, cornflour, salt, and vanilla until smooth. Slowly pour in the warm milk, whisking constantly.

Pour the mixture back into the pot and cook over medium-low heat, stirring continuously, until thickened (about 10–15 minutes). It should be a custard consistency.

3. Assemble:
Pour the filling into the pre-baked crust and smooth the top. Sprinkle with ground cinnamon.

Let it cool completely. For best results, refrigerate for at least 1 hour to set.