Put your frozen banana pieces in the food processor or blender and blend or pulse until it's tiny uniform pieces, or begins getting creamy.
Add the milk, vanilla, sea salt, cocoa powder, and cinnamon, and begin pulsing until the mixture comes together, then blend until it's creamy. You may need to add a tiny bit more milk to get it to the perfect consistency.
Serve immediately. You can also freeze it and eat later, though it will be harder.
