Preheat oven to 350°F (175°C). Line an 8x8-inch (20x20cm) baking pan with parchment paper. In a bowl, mix all-purpose flour, half the sugar, a pinch of salt, and melted butter until crumbly.

Press the dough evenly into the pan. Bake for 15-18 minutes until golden-brown.

Beat softened cream cheese and the remaining sugar for 2 minutes until smooth. Add egg and vanilla, beating on low just until combined.

Pour the smooth, dense filling over the warm baked crust and spread evenly.

Dollop warmed raspberry jam over the filling. Drag a butter knife through the dollops in a figure-eight motion to create a glossy swirl.

Bake for 22-25 minutes until the edges are set but the center still jiggles slightly.

Cool at room temperature for 1 hour, then refrigerate for at least 4 hours. Slice with a hot knife, and garnish generously with fresh raspberries and chopped roasted pistachios.