Pick the Perfect Melon: The success of this Chilled Melon Soup relies entirely on the sweetness of your fruit. Smell the stem end of the cantaloupe at the store; it should smell fragrant and sweet, and the stem scar should yield slightly to pressure.
Toast the Nuts: Do not skip toasting the pistachios! Toasting them in a dry pan for 2–3 minutes releases their essential oils and adds a nutty crunch that contrasts perfectly with the smooth texture of the soup.