In a food processor, pulse the flour with the confectioners' sugar and salt. Add the butter and pulse until the mixture resembles coarse crumbs. In a small bowl, whisk the egg yolk with the water. With the machine on, slowly add the egg yolk mixture and process just until the dough comes together. Turn the dough out onto a work surface and gently knead it 3 times. Pat the dough into a large disk. Wrap the disk in plastic and refrigerate for at least 1 hour or overnight.
In a large bowl, using a handheld electric mixer, beat the confectioners' sugar with the butter until creamy. Add the eggs, 1 at a time, beating thoroughly after each addition. Add the ground almonds, flour, rum and salt and beat at low speed until well blended. Cover and refrigerate the almond cream. Remove it from the refrigerator 15 minutes before using.
On a lightly floured surface, roll the dough out to a large round about 1/8 inch thick. Fit the dough into a 12-inch fluted tart pan with a removable bottom. Prick the bottom with a fork. Wrap the tart shell in plastic and refrigerate until chilled, at least 1 hour.
Preheat the oven to 375°. Line the tart shell with foil and fill it with pie weights or dried beans. Bake for about 20 minutes, or until lightly browned around the edges. Remove the foil and weights and bake the tart shell for about 20 minutes longer, or until the bottom is dry and the sides are nicely browned. 5. Using a spatula, spread the almond cream in the tart shell in an even layer. Bake for 20 to 25 minutes, until pale golden and firm in the center. Transfer the tart shell to a rack and let cool completely before filling with fruit.
Using a spatula, spread the almond cream in the tart shell in an even layer. Bake for 20 to 25 minutes, until pale golden and firm in the center. Transfer the tart shell to a rack and let cool completely before filling with fruit.
In a large bowl, gently toss the fruit with the sugar and lemon juice. Arrange the fruit on the tart just before serving.