Heat 2 cups of whole milk and 1 cup of heavy cream with ½ cup of sugar until simmering. In a bowl, whisk together remaining sugar, salt, cornstarch, and yolks until smooth. Slowly add warm milk mixture to egg mixture, whisking continuously. Return to saucepan, cook for about 2 minutes until thick. Remove from heat, add butter and vanilla, cool completely, then refrigerate for at least 2 hours.

In a food processor, combine 1 ½ cups of flour, ½ cup powdered sugar, and a pinch of salt. Add cubed butter, pulse until crumbly. In a bowl, whisk egg and vanilla, blend into flour mixture until a dough forms. Chill for 1 hour, then roll out and fit into a greased tart pan. Bake at 400°F for 10 minutes, lower to 350°F and bake for an additional 5-6 minutes until golden. Cool completely.

Once cream is chilled and crust is cool, spoon custard into tart shell. Arrange seasonal fruits decoratively on top, layering for a stunning visual effect.

Melt ½ cup of apricot preserves in a saucepan over low heat. Use a pastry brush to glaze the surface of the fresh fruit for a shiny finish.

Chill the assembled tart in the refrigerator for about 30 minutes to set. Serve immediately or refrigerate for up to 12 hours.