01 - Place frozen berries, banana, spinach, almond milk, and any optional add-ins (chia seeds, honey or maple syrup, cinnamon) into a blender.
02 - Blend on high speed until the mixture is completely smooth, scraping down the sides as needed.
03 - Taste and add sweetener if desired, blending briefly to incorporate.
04 - Divide the smoothie evenly into two glasses and serve immediately.