To make the pineapple crisps, boil the sugar and water together for about 10 minutes to make a syrup. Set aside to cool.
Skin the pineapple and slice crosswise as thinly as possible. Pat dry. Dip the pineapple slices in sugar syrup, and arrange on a lined baking tray. Dry them out until paper-thin and crispy in a preheated oven set to a very low temperature (120°C). Set aside to cool and store in air-tight jars if not using immediately.
To make tapai mousse: Combine the coconut milk, water and sugar in a saucepan and heat gently. While coconut milk mixture is cooking, whip the eggs until light and frothy. When the mixture comes to a boil, lower the heat and stir in the beaten eggs, fermented rice and rice wine. Stir until it sets. Set aside to cool.
Whip the cream until soft peaks form and fold into the cooled tapai mixture. Chill tapai mousse in the refrigerator.
To make palm sugar syrup, boil the palm sugar and water together until thick and syrupy.
To assemble, lay two pineapple crisps on a serving plate and place two scoops (about a tablespoon each) of chilled tapai mousse in the centre. Serve drizzled with palm sugar syrup and garnish with mint.