Add the spinach and blend briefly until the leaves are fully broken down and the mixture turns bright green.

Add the banana slices, frozen blueberries, cocoa powder, and vanilla extract.

Blend on high speed until the fruit is completely smooth and no spinach pieces remain visible.

Add the ice cubes and blend again until the smoothie becomes thick, creamy, and frosty.

Pause to scrape down the sides of the blender if needed for an even texture.

Taste and adjust consistency with a splash of milk if the smoothie is too thick.

Pour into chilled glasses and serve immediately while cold and creamy.