Pasticciotti Alla Crema (Italian Cream Filled Tarts)

Directions
Preparation:30min  ›  Cook:25min  ›  Extra time:1hour resting  ›  Ready in:1hour55min 

1. Pastry: Stir together the flour, sugar and ammonia then pour onto a work surface or leave in a large bowl. Make a well in the centre and add cubed butter, beaten eggs and vanilla. Quickly mix all the ingredients to make a smooth dough. Do not overwork. Wrap in plastic wrap and chill in the fridge for 1 hour.
2. Cream Filling: In a saucepan, heat up half of the milk until lukewarm.
3. In a bowl, whisk sugar and egg yolks together until frothy. Stir in lemon zest and then flour, a bit at the time. Keeping whisking, then gradually whisk in the 500ml lukewarm milk.
4. Pour everything back into the milk saucepan and place over low heat. Pour in the remaining milk, a little at the time, stirring constantly to prevent lumps. Cook until the mix becomes fairly thick and smooth. Cover and cool at room temperature while you roll out the pastry.
5. To Assemble and Bake: Preheat oven to 170 degrees C. Grease 15 (6-7cm) round mini cake moulds.
6. Cut the pastry into 4 equal pieces and work with one at the time (refrigerate the other 3 until it's time to use). Roll out one piece of pastry on a lightly floured surface to about 5mm thick, then cut out five 10cm rounds. Transfer each round to a prepared mould, covering bottom and sides. Proceed in the same way with the second and third portions of pastry, lining 15 moulds in total. With the fourth and last piece of pastry, roll out 15 (6-7cm) rounds and set them aside.
7. Prick with a fork the bottom of the pastry cases, then pour in the pastry cream, filling each 3/4 full. Cover with the reserved pastry lids and crimp the edges to seal. Prick the top to let steam out during baking. Brush lids with beaten egg white.
8. Bake in preheated oven for 20 to 25 minutes, or until puffy and lightly browned. Remove from oven, let cool and serve.

Ammonia

Also called baker's ammonia or bicarbonate of ammonia, ammonia is a leavening agent that was used before the advent of bicarbonate of soda and baking powder. It can be found in speciality shops and online.
Instead of ammonia, you can use 2 teaspoons baking powder OR 1 teaspoon baking powder and 1 teaspoon bicarbonate of soda.