01 - Place the cooled coffee, banana, milk, honey or maple syrup, vanilla extract, ice cubes, and oats (if using) into a blender canister.
02 - Blend on high speed for 30–45 seconds until completely smooth and creamy with no ice chunks remaining.
03 - Taste the smoothie and add additional sweetener if desired, then blend briefly to incorporate.
04 - Divide the mixture evenly between two glasses and serve right away while cold.