Put the allspice berries and cardamom pods in a large saucepan. Use the end of a rolling pin to gently split open the cardamom pods and crack the allspice into a few pieces. Add the remaining spices, coconut milk and 140g of the caster sugar to the pan. Set over a gentle heat and simmer for 5 mins. Cool, then chill overnight.
Grease 4 x 200ml pudding moulds, ramekins or pretty glasses with a little oil (you can skip this if you don’t want to turn the creams out once set). Put the remaining sugar, mango, and lime juice in a food processor and blend to a purée. Sieve the purée into a saucepan, sprinkle 1 tbsp agar agar flakes over the surface and leave to stand for 5 mins or until the agar agar has dissolved. Stir the agar agar into the purée and bring to a gentle heat, then simmer for 3-5 mins, stirring now and then, until the purée has thickened slightly. Divide between the moulds and chill for at least 2 hrs or until set.
Sieve the infused coconut milk into a clean pan and discard the spices. Sprinkle over the remaining agar agar flakes and leave for 5 mins until the agar agar has dissolved. Heat gently for 3-5 mins, stirring now and then. Divide the mixture between the moulds and chill for at least 4 hrs, or overnight.
To serve, dip the base of each mould into hot water for 10 secs or so, then turn out onto a plate. Top each dessert with a little chopped mango, some passion fruit seeds and a small sprig of mint, then sprinkle the coconut flakes around the plate.