Once upon a time, I bought a honeydew so overripe that, when I cut into it, I discovered more juice and less solid flesh than I'd ever seen in a melon before. The juice tasted like nectar, and I couldn't bear to consign the fruit to the compost pile. It more than made up in flavor what it had lost in texture, so I thought, "Why not soup?" That first bowl, a revelation, led to many others and, eventually, to this cantaloupe and yogurt soup with ginger, lime and spearmint from my garden. If your garden gives you basil, toss a few leaves into the soup, too. Use your favorite melon, or whatever looks best at the market: casaba, crenshaw, canary, orange or yellow or green. Serve it cold, on the hottest days, for breakfast or dessert.