Place bananas, ice, dates, vanilla, coconut milk, and 15g of the coconut oil into the Thermomix bowl and blend 1 min/speed 10.
Pour into serving glasses and place in the freezer while you make the sauce.
Place remaining coconut oil, cacao powder, coconut sugar and salt into the Thermomix bowl and heat 2 min/50°C/speed 2. Blend 20 sec/speed 5. Make sure the salt has blended into the sauce.
Serve sauce dolloped over cold smoothies with a slice of banana and coconut to garnish if desired. The sauce will set in the cold smoothie. It is divine!