For those of you who don't eat dairy, this is a nice substitute. You can add the cacao for a different type of whipped cream. If it's too stiff add a little of the reserved coconut milk from the can to thin it out.
Chill the coconut milk in the cans for at least 2 days.
Chill the bowl and beaters for an hour.
Open the coconut milk cans and remove the white coconut milk solids from the can. Put the liquid in another container and keep for other things.
On low speed whip up the thick white coconut milk solids for a minute and add the vanilla and sweetener to taste. If you do use Xyla, it might be good to grind it into a fine powder with a little arrowroot powder mixed in.
Once the coconut milk solids are whipped, slowly add the cacao (if using) by using a spoon and stir in. Then blend the mixture with a whip on high for another minute.
If you find this too thick, add a little of the watery coconut milk until it suits your needs.
You can eliminate the cacao if you wish and make this a vanilla topping.