In a large bowl, combine flour, powdered sugar, and salt.

Add cold cubed butter and rub it into the flour using your fingers or a pastry cutter until it resembles fine breadcrumbs.

Add egg yolk and sour cream, then mix until the dough just comes together. Don’t overwork it! If it is too dry, add a bit of water.

Shape into a disk, wrap in plastic wrap, and chill for 30 minutes.

Preheat your oven to 350°F (175°C).

Roll out the dough on a floured surface to fit a rectangular tart pan (or a shape of your choice). Press it gently into the pan and trim any excess.

Prick the base with a fork, place a sheet of parchment paper over it, and fill with baking weights (or dry beans).

Bake for 15 minutes, remove the weights, and bake for another 10-12 minutes until golden. Let it cool completely.

In a heatproof bowl, melt white chocolate gently over a double boiler or in the microwave in 15-second bursts, stirring in between.

Stir in pistachio paste and heavy cream until smooth.

Toast the kataifi (shredded fillo dough) in a dry pan over medium heat for 2-3 minutes until golden and crispy. Stir it into the filling along with powdered sugar and a pinch of sea salt.

Pour the filling into the cooled tart shell and spread evenly. Let it set in the fridge for 30-45 minutes.

Chop the white chocolate finely if using a bar.

Heat the heavy cream in a small saucepan or microwave just until warm (not boiling).

Pour over the chocolate and let it sit for a minute, then stir gently until smooth.

If it’s too thick, add a splash more cream until you get the perfect drizzling consistency.

Sprinkle crushed pistachios and freeze-dried raspberries on top.