01 - Blend flour, powdered 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 just comes together. Add more water only if needed. Flatten into a disk, wrap tightly in plastic, and refrigerate for minimum 1 hour.
02 - Roll chilled dough on lightly floured surface to fit 9-inch tart pan. Press dough evenly into pan, trim excess edges, and prick base thoroughly with fork. Refrigerate shell for 15 minutes while preheating oven to 350°F.
03 - Line chilled tart shell with parchment paper, fill with baking weights or dried beans. Bake for 15 minutes, carefully remove weights and parchment, then continue baking 10 minutes until golden brown. Cool completely before filling.
04 - Whisk mango puree, whole eggs, egg yolks, sugar, and lime juice in saucepan until smooth. Cook over medium-low heat, stirring constantly without stopping, until thickened approximately 10 minutes. Mixture is ready when coating back of spoon thickly.
05 - Remove pan from heat immediately. Add butter cubes, stirring until completely melted and incorporated. Press mixture through fine-mesh sieve for silkiest texture. Let cool slightly before filling.
06 - Pour cooled mango curd into completely baked tart shell, smooth top with offset spatula. Refrigerate uncovered minimum 1.5 hours until fully set and firm to touch.
07 - Top with fresh mango slices, toasted coconut flakes, and mint leaves immediately before serving. Serve chilled with whipped cream or coconut sorbet if desired.