In a food processor, add all the cold ingredients and pulse at low speed until the dough comes together in a ball.

Cover the dough with plastic wrap and let it set in the fridge for 30 minutes to 1 hour.

In a saucepan, add the milk, the lemon peels (only the yellow part), and the vanilla seeds or powder.

Bring to a simmer, then turn off the heat and let it rest for 10 minutes.

In a bowl, mix the sugar with the egg yolks, then add the flour.

Remove the lemon peels and vanilla pod if used, then pour a dash of milk into the bowl with the eggs to temper them. Mix and add a bit more.

Then pour the egg mixture into the saucepan with the milk and mix well.

Turn on the heat to low and keep whisking until the custard is thickened to the right consistency. Remove from heat.

Pour the custard into a bowl and cover with plastic wrap, letting it adhere well to the custard to avoid the creation of a film. Set it aside to cool down.

Preheat the oven to 320°F (160°C).

Dust a large wooden board with flour, then divide the dough into a smaller and a larger portion (about ⅓ and ⅔).

Knead the larger dough portion a bit (add more flour if it's sticky to the touch), then roll into a disc about ¼ inch (6 mm) thick.

Grease and dust with flour a 10 inch (26 cm) pie pan, when move over the pie dough.

Pierce the bottom with a fork, then pour over the cooled custard and spread it evenly.

Roll the remaining dough into a disc and place it on top of the custard. Seal the edges.

Brush the top with a bit of water, then sprinkle the pine nuts.

Bake in the middle-low rack of the oven for about 50 minutes or until slightly golden on top.

Let it cool down completely for a couple of hours before dusting with powdered sugar and serving.