Place the Coconut oil in a small saucepan and melt over a very low heat.
Add the maple syrup and whisk.
Add the cocoa and whilst til combined.
Stir until slightly thickened.
Pour the chocolate mixture into a lined container/tin and place in the freezer for 30 minutes, or until set.
Break the set chocolate into small pieces and place in a heatproof bowl.
Pour the cream into a small saucepan and bring to the boil over medium heat.
Pour the boiling cream over the chocolate and allow to sit for 5 minutes.
Add the 1 tablespoon of coconut oil and the vanilla extract and whisk until all the lumps are gone and the ganache is smooth and shiny.
Remove the tart from the fridge and pour the ganache over the mousse layer. Use a spatula or knife to smooth the surface.
Place the tart in the fridge for 1 hour to set before serving.