Line an 18 x 28cm slice tin with baking paper and set aside until needed.
Place the butter into your Thermomix bowl and cook for 3 minutes, 60 degrees, speed 2 to melt.
Add the Marie Biscuits and select the Turbo function. Blitz for 2 seconds 2 - 3 times or until the biscuits are crushed.
Add the cocoa, coconut and sweetened condensed milk and mix for 12 seconds, speed 5, REVERSE. You will need to use your spatula to help push the mixture down into the blades. If needed, combine for a further 10 seconds, speed 5.
Transfer the chocolate slice mixture to your prepared slice tin.
Break the white chocolate into pieces and place it along with the coconut oil into a microwave safe bowl and cook for 30 seconds spurts until it's just melted.
Carefully pour the melted chocolate over your chocolate slice and then decorate with the Easter Eggs and sprinkles.
Place the slice into the fridge for a minimum of 3 hours to firm before cutting into pieces.