Preheat oven to 350°F (175°C) and line your baking pan with parchment, leaving an overhang for easy lifting.

In a food processor, pulse 1 cup shelled pistachios, 2 cups flour, 3/4 cup sugar, and 1/4 tsp salt until finely ground.

Add 1 cup cold cubed butter and pulse until mixture forms pea-sized crumbs.

Add 1 beaten egg and pulse until the dough just starts to hold when pressed. Press the dough into the prepared pan.

Tip: For a crisper crust, blind-bake for 12-15 minutes until golden at edges.

In a bowl, beat 8 oz cream cheese until smooth. Add 1/2 cup sour cream, 1/2 cup powdered sugar, 1 tsp vanilla, and lemon zest, mixing well.

Fold in 1/2 cup finely chopped pistachios for texture.

Spread the cream-cheese mixture evenly over the cooled crust.

Chill in the refrigerator while preparing the jello/pudding layer.

For the jello layer, whisk the pistachio instant pudding mix with 1 1/4 cups cold milk until smooth. Let it thicken for 2-5 minutes, then spread over chilled cream layer.

Alternatively, prepare a gelatin layer by blooming unflavored gelatin in cold water, warming pistachio purée, and whisking everything together before pouring over the cream layer.

Refrigerate the assembled dessert for at least 4 hours, preferably overnight.

Before serving, whip 1 cup heavy cream to soft peaks, then pipe or dollop across the top, scattering pistachios and fresh berries.

Use a sharp knife dipped in hot water for clean slices.