Shuck the corn. Sweet corn soup is made with corn at the height of its ripeness in the summer. Take an ear of fresh corn and pull the leaves down to reveal the silk. Use your fingers to pull all the leaves and silk from the corn. Chop off the bottom knob with a sharp butcher knife.
Look for fresh corn at your grocery store or farmer's market in the summer months. Corn grown locally will have the best flavor, since it doesn't have to travel far.
This recipe tastes best with fresh corn, but you can use canned or frozen corn if you don't have fresh corn on hand. Make sure you use corn preserved without sugar or other additives, which could affect the flavor of the soup.