01 - In a large mixing bowl, combine flour, salt, and powdered sugar. Add diced cold butter and rub it in with your fingertips until the mixture resembles fine crumbs. Add the egg and work just until a homogeneous dough forms. Shape into a disk, wrap in plastic wrap, and chill for 30 minutes.
02 - Preheat the oven to 350°F. Roll out the chilled dough and line a 10-inch tart pan. Prick the base with a fork. Cover with parchment paper and fill with pie weights. Bake for 20 minutes. Remove weights and paper, then continue baking for 10 minutes until golden. Let cool completely.
03 - Heat the milk with vanilla bean (split and scraped) or vanilla extract until just simmering. In a separate bowl, whisk egg yolks with sugar until pale, then add cornstarch and mix until smooth. Gradually whisk in a little hot milk to temper, then pour the mixture back into the saucepan. Cook over medium heat, stirring constantly, until thickened. Remove from heat, whisk in butter until smooth, and cover directly with plastic wrap. Allow to cool completely.
04 - Wash, hull, and slice the fresh strawberries as desired.
05 - Spread the cooled pastry cream in an even layer over the cooled tart shell. Arrange strawberry slices decoratively over the cream.
06 - Gently heat apricot jam with water until liquid. Brush the warm glaze evenly over the strawberries for a glossy finish.
07 - Chill the tart for at least 1 hour before slicing and serving.