Add Greek yogurt, banana, frozen mixed berries, spinach (if using), and almond milk to a blender.
Drizzle in honey or maple syrup for sweetness, and sprinkle in chia seeds for extra texture and nutrients.
Blend until smooth and creamy.
Adjust consistency — add more milk if it’s too thick, or add ice cubes for a thicker, frothier smoothie.
Taste and adjust sweetness if desired.
Pour into a glass, garnish with berries or chia seeds, and enjoy immediately!