01 - Place bananas, milk, maple syrup or honey, vanilla extract, and ice cubes into a blender.
02 - Blend the mixture until completely smooth and frothy, about 30 seconds.
03 - Taste and add more sweetener if desired, blending briefly to incorporate.
04 - Divide the shake evenly between two chilled glasses.
05 - Top with whipped cream, banana slices, and a sprinkle of ground cinnamon if desired. Serve immediately.