Cinnamon Biscuit Base:

1. Preheat oven to 180°C (350°F).
2. Grease a 16 x 25cm slice pan and line the base with parchment paper.
3. In a bowl, mix flour, coconut, brown sugar, and cinnamon.
4. Add melted butter and stir until combined.
5. Press mixture evenly into the prepared pan.
6. Bake for 12 minutes until golden. Let cool.

Dark Hot Chocolate Mousse:

1. Melt butter, cocoa, and chocolate in a small saucepan over low heat, stirring until smooth.
2. Remove from heat and quickly mix in egg yolks. (The mixture may look lumpy but will smooth out when cream is added.)
3. In a separate bowl, whisk egg whites, gradually adding sugar until stiff peaks form.
4. Gently fold a spoonful of the chocolate mixture into the egg whites, then fold in the rest.
5. Fold in whipped cream until fully combined.
6. Pour mousse over the cooled biscuit base, smoothing the top.
7. Refrigerate for 4 hours until set.

Vanilla Marshmallow:

1. In a small saucepan, combine sugar, water, and gelatine over low heat, stirring until dissolved.
2. Increase heat to medium and simmer for 6 minutes, stirring occasionally. Let cool for 5-10 minutes.
3. Pour mixture into a stand mixer and beat on high for 9 minutes until thick, white, and fluffy.
4. Mix in vanilla extract.
5. Spread marshmallow over the set mousse layer, smoothing the top.
6. Refrigerate for 4 more hours until firm.

To Serve:

1. Heat a knife in hot water, wipe dry, and slice.
2. Store in an airtight container in the fridge for up to 3 days