01 - Blend flour, powdered sugar, and salt in a food processor. Add cold butter and pulse until mixture resembles coarse breadcrumbs. Add egg yolk and 1 tablespoon cold water, pulsing until dough just comes together. Add more water only if necessary. Flatten into a disk, wrap in plastic, and refrigerate for at least 1 hour.
02 - Roll chilled dough on lightly floured surface to fit 9-inch tart pan. Press dough into pan evenly and trim excess edges. Prick base thoroughly with fork. Chill shell for 15 minutes while preheating oven to 350°F.
03 - Line tart shell with parchment paper and fill with baking weights or dried beans. Bake for 15 minutes, then carefully remove weights and parchment. Continue baking for 10 minutes until golden brown. Allow to cool completely.
04 - Whisk mango puree, eggs, egg yolks, sugar, and lime juice in saucepan. Cook over medium-low heat, stirring constantly for approximately 10 minutes until mixture thickens enough to coat back of spoon. Remove from heat immediately.
05 - Stir butter cubes into hot curd until completely melted and smooth. Pass mixture through fine mesh sieve for silky texture. Transfer to clean bowl and let cool slightly.
06 - Pour mango curd into cooled tart shell, spreading evenly. Refrigerate for at least 1.5 hours until completely set.
07 - Garnish with fresh mango slices, toasted coconut flakes, and mint leaves just before serving. Serve chilled with whipped cream or coconut sorbet if desired.