[To make pastry:] Mix flour, salt and sugar together in a mixing bowl. Rub in butter with fingertips until mixture resembles fine breadcrumbs. Add lightly beaten egg yolks, vanilla essence and blend well. Add in water to combine the mixture into a firm dough. Knead pastry until smooth.
Roll dough out on a floured surface into 3mm thickness and cut into 5cm circles with a pastry cutter. Line tartlet moulds with pastry and refrigerate for 30 minutes.
Prick base of tartlets and bake blind in a preheated oven at 190 ºC for 10 minutes. Remove paper and beans and continue to bake five minutes more until pastry is golden brown.
Leave tartlet cases to cool in the moulds before turning out onto a wire rack to cool completely.
Spoon custard filling into prepared tartlet cases and decorate with fruits as desired. Brush over with glaze to give it a shine and also to preserve the fruits.
[To make filling:] Heat milk in a deep saucepan until warm and sugar has dissolved. Pour half amount of warm milk into the corn flour mixture. Stir well then add to the remaining milk and bring to a low boil. Keep stirring until mixture starts to thicken. Remove from heat and add in the vanilla essence.
[To make glaze:] Mix the apricot jam and water together and heat to dissolve. Keep stirring until mixture is smooth. Brush fruit topping of tartlet with warm glaze immediately.