Creating Mini Fruit Tarts With Pastry Cream is a simple yet enjoyable process. Follow these detailed steps for success:

For the Tart Shells:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Mix the Dough: In a food processor, combine flour, sugar, and salt. Add the cold butter and pulse until the mixture resembles coarse crumbs.
3. Add Egg Yolks and Water: Add the egg yolk and 2 tablespoons of ice water, pulsing until the dough starts to come together. If needed, add another tablespoon of water.
4. Form the Dough: Gather the dough into a ball, flatten slightly, wrap in plastic wrap, and refrigerate for at least 30 minutes.
5. Roll and Cut: On a lightly floured surface, roll out the chilled dough to about 1/8 inch thick. Cut into circles to fit into your mini tart pans.
6. Fit into Pans: Press the dough circles into the sides of the mini tart pans. Prick the bottom of each shell with a fork to prevent puffing during baking.
7. Blind Bake: Place a piece of parchment paper over the tart shells and fill with pie weights or dried beans. Bake for 15-20 minutes until lightly golden. Remove weights and parchment, then cool completely.

For the Pastry Cream:

1. Heat Milk: In a medium saucepan, heat the milk over medium heat until almost boiling.
2. Mix Sugar and Cornstarch: In a bowl, whisk together the sugar, cornstarch, and egg yolks until smooth and pale.
3. Temper the Mixture: Gradually add a small amount of the hot milk to the egg mixture, whisking constantly to temper the yolks.
4. Cook the Cream: Pour the egg mixture back into the saucepan with the remaining milk. Cook over medium heat, whisking constantly until thickened.
5. Add Butter and Vanilla: Once thick, remove from the heat and stir in the butter and vanilla extract. Transfer to a bowl, cover with plastic wrap directly on the surface to avoid a skin forming, and let cool.

Assembly:

1. Fill Tart Shells: Once the tart shells and pastry cream are cooled, fill each shell with pastry cream, smoothing the top with a spatula.
2. Top with Fruits: Arrange the assorted fresh fruits on top of the pastry cream. Be creative and mix different colors and shapes for an attractive presentation.
3. Chill: Refrigerate the assembled tarts for at least 30 minutes to allow the flavors to meld.