Whisk the flour, granulated sugar, and salt together in a large mixing bowl. Add the cold butter cubes and rub in with your fingertips until the mixture looks like coarse crumbs.

Add the egg yolk and vanilla extract, mixing with a fork until the dough starts to clump together. Add ice water only if the dough feels dry, a tablespoon at a time.

Bring the dough together into a ball, flatten into a disk, wrap, and chill for 30 minutes.

Heat the oven to 180 C / 356 F and line a 33 x 23 cm / 13 x 9-inch sheet pan with parchment.

Roll the chilled dough on a lightly floured surface into a rectangle about 33 x 23 cm, roughly 4 mm thick. Cut in half to make two equal rectangles and transfer both to the sheet pan, leaving space between them.

Prick both pastry sheets all over with a fork. Bake for 14 to 16 minutes, until pale gold at the edges and still pale in the center.

Cool completely on the pan for 10 minutes, then transfer to a wire rack.

Spread the raspberry jam evenly over one baked pastry sheet, leaving a small border. Top with the second pastry sheet, pressing gently to help them stick together.

Whisk the powdered sugar and lemon juice together until smooth and thick enough to hold a ribbon shape for a few seconds. Spread over the top layer with an offset spatula.

Sprinkle the chopped pistachios in a line down the center while the glaze is still wet. Let sit at room temperature for 15 to 20 minutes until the glaze is firm to the touch.

Cut into 16 bars with a sharp knife dipped in hot water, wiping the blade clean between cuts.