Preheat oven to 350°F. Using fork, mix flour, 1/2 cup powdered sugar, melted butter, and coconut in medium bowl until dough forms. Divide into 6 equal pieces. Press each piece onto bottom and up sides of 4 1/2-inch-diameter tartlet pan with removable bottom. Chill crusts 30 minutes. do ahead Can be made 1 day ahead. Cover and chill.
Bake crusts until golden, pressing down with spoon if bubbles form, about 25 minutes. Cool.
Purée 2 mangoes in processor. Measure 13/4 cups puree; mix in spices.
Transfer to bowl; cover and refrigerate.
Pour lime juice into small saucepan; sprinkle gelatin over.
Let stand until gelatin softens, about 10 minutes. Stir over low heat just until gelatin dissolves, about 2 minutes.
Remove from heat.
Whisk in condensed milk, then spiced mango puree. Divide filling among cooled crusts. Chill at least 3 hours and up to 5 hours.
Using electric mixer, blend egg whites and coarse salt in large bowl. Gradually add 1 1/2 cups powdered sugar; beat until stiff peaks form, about 5 minutes.
Spoon meringue atop tartlets or pipe atop tartlets using pastry bag fitted with large star tip. Using butane torch, lightly brown meringue. (Alternatively, place tartlets in 500°F oven until meringue is golden in spots, watching carefully to prevent burning, about 3 minutes.)
Garnish with remaining mango slices and mint sprigs.
