Start by washing the berries thoroughly if they are fresh. Peel and slice the banana into smaller pieces so it blends evenly. Measure all ingredients before starting to keep the process quick and smooth.
Pour the apple juice and yogurt into the blender first to help the blades move easily. Add the berries, banana slices, ground flaxseed, and honey if using. Ice cubes should go in last if needed.
Blend everything on high speed for 30 to 45 seconds. Stop once to scrape down the sides if needed. The mixture should look thick, smooth, and evenly blended with no chunks.
If the smoothie is too thick, add a splash of apple juice or water and blend again. If it’s too thin, add a few more frozen berries. Blend briefly until the texture feels just right.
Pour the smoothie into a chilled glass and serve right away. Freshly blended smoothies taste best and have the creamiest texture.