To cut mango into pieces, stand it on end and slice the flesh off both sides of the central pit. Lay each half on a cutting board and with the tip of your knife, score the flesh in a cross-hatch pattern. Pushing from the skin side, turn inside out so that the mango flesh pops up; slice it off the skin. Also cut off the remaining flesh from around the pit and remove the skin.
In a blender, puree the fruit and ginger, scraping down the sides as necessary. Add the buttermilk, yogurt and ice and puree until smooth and frothy. Pour into glasses.