Put the coconut fat and the chocolate in a casserole an melt it slowly. Take away the casserole from the stow and let the liquid cool down for 5 minutes.
Put the icing sugar and the eggs in a bowl and mix until fluffy with an electrical mixer.
Add the chocolate liquid in the egg and sugar mixture while stirring slowly at the same time.
Take out a rectangular baking form. Pour some chocolate in the form so it cover the bottom. Add some Marie biscuits on top of the chocolate. Continue with layers of chocolate and the biscuits, and finish with a layer of chocolate.
Place the cake in the fridge for minimum three hours before serving.