HOW TO CLEAN AN AVOCADO Make sure you wash your avocados before slicing them open. To cut them open and into slices: Slice down the center lengthwise with a sharp knife. Slice until the knife reaches the pit. With a steady knife, slowly turn the avocado. Your knife should cut the peel and the flesh around the pit. Twist the two halves to separate. Scoop out the pit with a spoon and you’re ready to scoop out the flesh.