In a saucepan large enough for all the ingredients, mix together the water, cocoa powder, 2.5 tablespoons of sugar, salt and vanilla. This will create a paste.
2 tablespoons water, 2 1/2 tablespoons (21 grams) unsweetened Dutch-process cocoa powder, 2 1/2 - 3 tablespoons granulated sugar, 1/8 teaspoon salt, 1 teaspoon vanilla extract
Then stir in the coconut and cashew milk.
1/2 cup (120 ml) full-fat coconut milk, 1/2 cup (120 ml) unsweetened cashew milk
Turn the heat to medium-high and heat, stirring occasionally, until warm enough for your liking. Add more sugar, if desired.
If you have leftovers, cool completely, cover and refrigerate for up to 4 days.