Wash the apple thoroughly, remove the core, and chop it into small pieces. Peel the banana and gather the remaining ingredients.
Add the almond milk and Greek yogurt to the blender first.
Add the chopped apple, banana, rolled oats, cinnamon, almond butter, vanilla extract, honey (if using), and ice cubes.
Blend on high speed for 45–60 seconds until smooth and creamy.
Taste the smoothie and adjust the sweetness by adding a little more honey or maple syrup if desired.
Pour into chilled serving glasses, sprinkle a pinch of cinnamon on top, and enjoy immediately.