Rinse the fresh blueberries under the cold running water. Measure out the matcha powder and ice cubes. (If using frozen berries, there's no need to thaw them beforehand. )
Place the blueberries, almond milk, ice cubes, oatmeal, matcha powder, and banana in the blender. Blend until creamy texture and well-combined, or until you reach the desired consistency. You can adjust the quantities of each ingredient to suit your taste preferences.
Pour the matcha berry smoothie into glasses and garnish with fresh berries or a light dusting of matcha powder on top, if desired.
Serve the matcha berry smoothie immediately while it's fresh and cold. Enjoy your homemade matcha berry smoothie!