Preheat your oven to 180°C (160°C fan-forced) and grease a 20cm springform cake pan. In a food processor, combine shortbread biscuits, shredded coconut, and chopped pistachios. Pulse until the mixture resembles coarse crumbs, then mix in melted unsalted butter and icing sugar until well combined. Press this mixture firmly into the base of the pan and bake for 15 minutes, or until golden brown. Allow it to cool completely.

In a small bowl, sprinkle gelatine powder over the specified amount of water, making sure it’s evenly distributed. Allow it to sit for about 5 minutes to bloom.

In a saucepan, heat the milk over medium heat until it just begins to simmer; then remove from the heat. Stir in the bloomed gelatine until fully dissolved. Place white chocolate in a mixing bowl and pour the warm milk mixture over it, letting it sit for 5 minutes to soften. Stir until smooth and incorporated.

In a separate bowl, whip the thickened cream until firm peaks form. Gently fold in the cooled chocolate mixture, then fold in chopped pistachios and glace cherries.

Carefully pour the mousse mixture over the cooled biscuit base. Smooth the surface with a spatula, cover with plastic wrap, and refrigerate for a minimum of 4 hours, or overnight.

Once the mousse has set, whip additional cream to firm peaks and decorate with a piping bag. Adorn with extra glace cherries, chopped pistachios, and sprinkle silver and gold cachous.