How to Help Prevent Cut Avocados from Darkening
Cut avocados lengthwise in half; remove and discard pits. Place avocado halves, cut sides down, in a shallow dish partially filled with water mixed with a few tablespoons of lemon juice. Refrigerate up to 12 hours. It's a great way to prepare avocados ahead of time for salads. Cut avocados as desired just before serving.