01 - Combine flour, salt, and confectioners' sugar in a large mixing bowl. Add cold diced butter and work with fingertips until mixture resembles coarse crumbs. Add the egg and mix just until the dough comes together. Shape into a ball, wrap in plastic, and refrigerate for 30 minutes.
02 - Preheat oven to 350°F. Roll out chilled dough and line a 9- or 10-inch tart pan. Prick base with fork. Line with parchment and fill with pie weights. Bake for 20 minutes. Remove weights and paper, continue baking for 10 minutes until pale golden. Let cool completely.
03 - Gently heat whole milk and vanilla in a saucepan until it just begins to simmer. In a separate bowl, whisk egg yolks with sugar until pale. Add cornstarch and blend until smooth. Gradually whisk in some hot milk, then pour mixture back into the saucepan. Cook, whisking over medium heat until thickened. Remove from heat and incorporate butter. Cover directly on surface with plastic and cool completely.
04 - Wash, hull, and slice strawberries as desired for decoration.
05 - Spread cooled pastry cream into the tart shell. Artfully arrange sliced strawberries on top.
06 - Warm apricot jam with water in a small pan until fluid. Gently brush over the strawberries to give a glossy finish.
07 - Refrigerate assembled tart for at least 1 hour before slicing and serving.