Blend ¼ cup non-dairy milk, cocoa powder, and bananas in a blender until smooth but still thick. If the nice cream isn't blending well enough, add up to ¼ cup more of non-dairy milk. Remember not to add too much, though. You want it to blend, but not become liquidy like a smoothie.
Serve the nice cream in two bowls and top with a zested chocolate chip and/or maraschino cherries, if using.