Heat the cream in a saucepan over a medium high heat then add the sugar and stir to dissolve. Bring to a simmer and stir continuously for about 3 to 4 minutes. Remove from the heat and vigorously whisk in the lemon zest and juice then allow to cool slightly.
Place a few raspberries in the base of 8 small ramekin dishes, or other small pots or cups then pour the cream mixture over top. Place in the fridge to set, about 8 hours or overnight. To serve, sprinkle with finely chopped pistachio nuts.