Cover the base of a 9 inch deep pie pan with aluminium foil. Brush the base and sides with ghee. Set aside.
Using a food processor, pulse the crushed biscuits into a smooth powder. Warm the ghee in a microwave for 45 seconds. Let it cool to room temperature. Gently pour the ghee over powdered biscuit and mix well to combine.
Using a spoon, spread the crust over the base of the pan. Press it gently with the smooth side of the spoon and create an even layer. Chill it in the fridge until the cheese base is ready.
Mix the gelatin in hot water. Blend together crumbled paneer, yogurt, condensed milk, cardamom powder and gelatin to a smooth paste.
Slice the gulab jamun into halves. Remove the pie pan from fridge and place a layer of gulab jamun as shown in the picture.
Sprinkle the pistachios and lemon zest. Pour the cheese mixture on top and let it set in the fridge for minimum 6-8 hours or overnight.
Using a spatula, gently release the sides and gently remove the base by unlocking the pan. Serve cold.