Instructions
- Preheat oven to 325°F (160°C).
- To make the Pâte Sablée Crust, combine flour, powdered sugar, and fleur de sel in a food processor. Pulse in butter until mixture resembles coarse crumbs. Mix in egg yolk, then gradually add ice water until dough comes together. Flatten into a disc, wrap in plastic wrap, and chill for at least 30 minutes. Roll out dough and place in a 9-inch tart pan with removable bottom. Prick the bottom with a fork and blind bake for 15-20 minutes, or until golden brown.
- To make the Lemon Curd Filling, whisk together sugar, cornstarch, and fleur de sel in a saucepan. Add water and cook over medium heat, stirring constantly, until thickened. Stir in lemon juice, lemon zest, and egg yolks. Cook for 1 minute more. Remove from heat and whisk in butter until smooth. Strain through a fine-mesh sieve.
- Pour Lemon Curd Filling into baked tart shell.
- To make the Italian Meringue, combine sugar and water in a saucepan and cook to 240°F (115°C) on a candy thermometer. While sugar syrup is heating, beat egg whites with cream of tartar until soft peaks form. Slowly pour hot sugar syrup into egg whites, beating constantly until stiff, glossy peaks form. Beat in cooled browned butter and vanilla bean paste.
- Spread Italian Meringue over Lemon Curd Filling, creating decorative swirls. Use a kitchen torch to lightly brown the meringue.
- Let cool completely before serving.
