01 - Pulse flour, sugar, and salt in a food processor. Add cold butter and pulse until mixture resembles coarse crumbs. Add egg yolk and 1 tablespoon cold water, pulsing until dough forms a ball. Add additional water only if necessary. Shape dough into a disc, wrap tightly in plastic wrap, and refrigerate for minimum 30 minutes.
02 - Roll chilled dough on floured surface to 1/8-inch thickness. Press dough into 9-inch tart pan, trimming excess. Prick bottom thoroughly with fork. Refrigerate 15 minutes. Preheat oven to 375°F. Line crust with parchment paper and fill with pie weights. Bake 15 minutes, remove weights and parchment, continue baking 8-10 minutes until golden brown. Cool completely before filling.
03 - Heat milk in medium saucepan over medium heat until just simmering. Meanwhile, whisk egg yolks, sugar, and cornstarch in heat-proof bowl until mixture thickens and turns pale yellow, approximately 2 minutes.
04 - Slowly stream one-third of hot milk into egg mixture while whisking constantly. Return tempered mixture to saucepan with remaining milk. Cook over medium heat, whisking continuously, until mixture boils and thickens significantly, about 2-3 minutes. Remove from heat immediately.
05 - Stir butter and vanilla extract into hot pastry cream until butter melts completely. Transfer to clean bowl, press plastic wrap directly onto surface to prevent skin formation. Refrigerate until completely cold, at least 2 hours.
06 - Spread cold pastry cream evenly into cooled tart crust. Arrange fresh fruit in decorative pattern over cream surface, overlapping slightly for visual appeal.
07 - Combine apricot jam with water in small saucepan. Warm over low heat until melted and smooth. Press through fine-mesh strainer to remove solids. Brush warm glaze lightly over fruit arrangement using pastry brush. Refrigerate assembled tart minimum 30 minutes before serving.