To dream of peppermint represents an aspect of your personality that feels "positiver" than before. It may reflect feelings of new superiority or an awareness that something has improved. Situations that allow to know something is better than it used to be.
To dream of peppermint candy represents pleasant feelings about oneself being "positiver." You feel good knowing your better than someone or that you've improved yourself in some way.
Example: One person dreamed of light green mint candy after discovering a cure to a long standing health problem. The mint candy represented their positive outlook on their improved health.