Steps for the apple and custard tart

• Heat the milk in a saucepan (you can flavor it with lemon zest or vanilla).
  In a bowl, quickly mix the eggs with the sugar, incorporate the cornstarch (or flour).
  Temper the egg mixture with a ladle of warm milk, mixing well to avoid lumps.

  Pour the mixture into the saucepan with the rest of the warm milk. Cook over medium-low heat, stirring continuously with a whisk until the custard thickens.

  Immediately transfer the custard to a wide, shallow container. Cover directly with plastic wrap to prevent a skin from forming on the surface.
  Let it cool.

  

• In a bowl, work the soft butter with the sugar and lemon zest until you get a creamy mixture.
  Add the flour and start working…the dough will seem sandy.

  Incorporate the egg and a pinch of salt.
  Quickly work the ingredients until a smooth and homogeneous dough forms. Don’t get discouraged: initially, it will seem not to come together, but persist for a few minutes until it becomes uniform.
  Wrap the dough in plastic wrap and let it rest in the fridge for at least 30-60 minutes.

  

• Ensure the custard is well-chilled and that the shortcrust has completed its resting time.
  Roll out the shortcrust dough with a rolling pin on a lightly floured surface and use it to line the tin. Trim the edges.
  Fill the shortcrust shell with the custard and smooth it well.
  Peel the apples and cut them into thin slices. Immediately drizzle them with lemon juice to prevent browning.
  Arrange the apple slices on the custard, placing them in a radial pattern or as desired.
  Use the remaining shortcrust to create strips, hearts, or other decorations to apply to the surface.

  

• Bake the tart in a preheated oven at 350°F in static mode.
  Bake for about 40-45 minutes.
  Once baked, it is crucial to let the tart cool completely inside the tin before removing it. This prevents breaking and ensures the custard sets perfectly.