Chowder with clams, sweet potatoes, and corn

A lot went into this chowder, but the end result was great. We began by sauteing a mire poix of leeks and onions in butter. Then we added crab stock, water, and sweet potato. When the potato was soft, we separated the soup, and, using the immersion blender, we blended half of it with cream until smooth. Meanwhile, we steamed open some clams and removed the from their shells. We combined the clams, the blended soup, the unblended vegetables, and a can of corn. We adjusted the salt, stirred in chopped parsley, and enjoyed the excellent meal.