Preheat your oven to 350°F (175°C) and grease and flour mini tartlet pans.

In a food processor, combine all-purpose flour and powdered sugar. Add cold cubed butter and pulse until it resembles coarse crumbs. Incorporate the egg yolk and ice water, pulsing until a dough forms.

Roll the dough into a ball, flatten it into a disk, wrap in plastic wrap, and refrigerate for at least 30 minutes.

On a floured surface, roll out the chilled dough to about 1/8-inch thickness. Cut out circles and press them into the tartlet pans. Bake for 10-12 minutes or until golden brown. Allow them to cool completely.

Pulse the shelled pistachios in the food processor until finely ground. In a mixing bowl, combine ground pistachios with heavy cream, powdered sugar, vanilla extract, and softened butter. Beat until smooth and creamy.

Spread a layer of cherry jam into each tartlet shell. Pipe or spoon the pistachio filling generously on top of the jam.

Garnish each tartlet with fresh cherries and sprinkle with crushed pistachios.