01 - Combine flour, salt, and powdered sugar in a mixing bowl. Add cold butter and rub gently with fingertips until the mixture forms coarse crumbs. Incorporate the egg and blend until a smooth dough forms. Shape into a ball, wrap in plastic, and chill for 30 minutes.
02 - Preheat oven to 350°F. Roll out pastry and line a 9 to 10-inch tart pan. Prick the base with a fork, cover with parchment, and fill with baking weights. Bake for 20 minutes, remove weights, and bake an additional 10 minutes until lightly golden. Cool completely.
03 - Heat milk and vanilla in a saucepan until just simmering. In a separate bowl, whisk egg yolks and sugar until pale, then incorporate cornstarch. Gradually add a small amount of warm milk to temper. Return all to the pan and cook over medium heat, stirring, until thickened. Remove from heat and stir in butter until smooth. Cover with plastic wrap directly on the surface and cool completely.
04 - Wash, hull, and slice the strawberries as desired.
05 - Spread chilled pastry cream evenly in the cooled tart shell. Arrange strawberries decoratively on top.
06 - Warm apricot jam with water until liquefied. Brush the glaze gently over the strawberries for a glossy finish.
07 - Refrigerate assembled tart for 1 hour before serving to allow flavors to meld.