When kale is tiny, you just barely need to wilt it. And when it's older and bigger, you change your methods. It goes into the soup. Maybe it gets pureed. But that happens with all fruits and vegetables.
Weather matters too.
A cold snap brings out the flavor. Ask at the farmers' market or check with the grocer to find out where your greens are grown. Other vegetables are green with envy. Collard greens, kale, spinach, Swiss chard and turnip greens have the rare distinction of being calcium -rich. Greens are also a great source of vitamin C , iron and folate .