In a large bowl, whisk together the flour and powdered sugar. Add the cold, cubed butter and use a pastry blender or your fingers to cut the butter into the flour until the mixture resembles coarse crumbs.

In a small bowl, whisk together the egg yolk and 2 tablespoons of ice water. Add this to the flour mixture and mix until the dough just comes together. If it's too dry, add the remaining tablespoon of ice water.

Form the dough into a disc, wrap it in plastic wrap, and refrigerate for at least 30 minutes.

On a lightly floured surface, roll out the chilled dough to a 12-inch circle. Carefully transfer the dough to a 9-inch tart pan with a removable bottom. Press the dough into the bottom and up the sides of the pan. Trim any excess dough from the edges.

Prick the bottom of the crust with a fork. Line the crust with parchment paper and fill it with pie weights or dried beans. Bake in a preheated oven at 375°F (190°C) for 15 minutes. Remove the parchment paper and pie weights, and bake for another 5-7 minutes, or until the crust is lightly golden. Let the crust cool completely.

In a medium saucepan, whisk together the granulated sugar and eggs until well combined. Stir in the lemon juice, butter, and lemon zest. Cook over medium heat, stirring constantly, until the mixture thickens enough to coat the back of a spoon. This usually takes about 5-7 minutes.

Remove the lemon filling from the heat and pour it through a fine-mesh sieve into a clean bowl. Let the filling cool slightly.

Pour the lemon filling into the cooled tart crust. Arrange the fresh raspberries on top of the lemon filling in a decorative pattern.

Refrigerate the Raspberry Lemon Tart for at least 2 hours to allow the filling to set completely.

Before serving, dust the tart with powdered sugar, if desired. Carefully remove the tart from the pan by lifting it up from the removable bottom. Slice and enjoy.