01 - Blend flour, powdered sugar, and salt in a food processor. Add cold butter cubes and pulse until mixture resembles coarse breadcrumbs. Add egg yolk and 1 tablespoon cold water, pulsing until dough just comes together. Add remaining water if dough is too dry.
02 - Shape dough into a flat disk, wrap tightly in plastic wrap, and refrigerate for at least 1 hour until firm.
03 - Roll out chilled dough on a lightly floured surface to fit a 9-inch tart pan. Press dough evenly into pan, trim excess edges, and prick base with a fork. Return to refrigerator for 15 minutes.
04 - Preheat oven to 350°F. Line tart shell with parchment paper and fill with pie weights or dried beans. Bake for 15 minutes, remove weights and paper, then continue baking for 10 minutes until golden brown. Cool completely.
05 - Whisk together mango puree, eggs, egg yolks, sugar, and lime juice in a saucepan. Cook over medium-low heat, stirring constantly, for about 10 minutes until mixture thickens enough to coat the back of a spoon.
06 - Remove from heat and whisk in butter cubes until completely melted and smooth. Strain curd through a fine mesh sieve for extra silky texture.
07 - Pour cooled mango curd into baked tart shell, smoothing top with an offset spatula. Refrigerate for at least 1.5 hours until completely set.
08 - Top with fresh mango slices, toasted coconut flakes, and mint leaves just before serving. Serve chilled.