In a mixing bowl, combine icing sugar, pastry flour, almond flour, and a pinch of salt. Cut in cold unsalted butter until it resembles coarse crumbs. Beat one egg and stir it into the mixture until a dough forms. Shape into a disc, wrap in plastic, and refrigerate for at least 30 minutes.

Remove the dough and roll between silicone mats to about 2mm thick. Cut out circles and press into greased muffin pans. Freeze for 1 hour.

Preheat oven to 180°C (356°F). Remove shells from freezer, line with parchment and fill with weights. Bake for 15 minutes, reduce temperature to 160°C (320°F) and bake for another 10-15 minutes until golden.

In a bowl, combine icing sugar and egg yolks, mix in cornstarch. In a saucepan over low heat, combine cream cheese, butter, milk, and parmesan. Pour warm mixture into egg mixture while whisking. Cook until thickened, then let cool.

Fill tart shells with cheese filling, and brush tops with egg wash.

Increase oven to 220°C (428°F) and bake for 5-10 minutes until tops are caramelized. Let cool before removing from pans.