In a 3-1/2- or 4-quart crockery cooker gradually stir water into white sauce mix until mixture is smooth. Stir in frozen potatoes, the 3 leeks, Canadian-style bacon or ham, evaporated milk, and dillweed.
Cover; cook on low-heat setting for 7 to 9 hours or on high-heat setting for 3 1/2 to 4-1/2 hours.
If using low-heat setting, turn to high-heat setting. In a medium bowl stir about 2 cups of the hot potato mixture into the sour cream. Return sour cream mixture to cooker. Cover and cook about 10 minutes more on high-heat setting or until heated through. Ladle into bowls. Sprinkle with parsley or additional sliced leek, if desired. Makes 10 to 12 side-dish servings.