Peel your bananas and pop into a blender. Slice your apples into hunks, discarding core and stem (peel first if you like or leave the peel on for extra goodness). Add to the blender with the dates (pitted first, if needed), cinnamon and a sliver or two of the ginger. Add 400ml water. Blend till smooth, adding more water if needed.
TIP: if you like and have it to hand, swap the water for milk (any kind or 50/50 mix of yogurt and water).