In a large bowl, beat the cream until it begins to thicken and forms very soft peaks. Avoid overbeating. Add the sugar, mashed avocado, and passion fruit puree. Mix well and set aside.
In a small microwaveable bowl, soak the gelatin in 45ml of water. Then heat in a microwave at 30-second intervals until the gelatin dissolves. Carefully add to the passion fruit mixture. Line a loaf pan with cling film. Place the avocado cubes on the bottom, followed by half the passion fruit mixture, half the raspberries, and the remaining passion fruit mixture. Smooth the top and freeze for 12 hours or overnight.
Unmould onto a serving platter, and discard the cling film. Let rest for 10 minutes before serving.