If you have a Vitamix, add the coconut milk and rice milk to the blender, along with maple syrup, cocoa powder, chocolate chips, vanilla and salt. Blend on high for several minutes until 100% smooth. If you have a Vitamix, this will work perfectly. If your blender is so-so, then I would suggest melting the chocolate chips first. Simply add the chocolate chips to a bowl with 1/2 cup of the milk and heat in the microwave or over a double boiler just until the chocolate is almost melted. Stir until smooth and then blend with the rest of the ingredients.
Pour the chocolate milk into a container and chill for several hours or overnight is preferred. Then it will be creamy, thickened perfectly and so chilled and delicious! Nothing quite like a super cold glass of chocolate milk. It makes a good amount too! It's very rich, so I find a small amount so satisfying.