In a 5 quart Dutch oven over medium heat, in hot water, cook onions
until tender. Add water, potatoes, and seasonings. Reduce heat to low; cover and simmer for 15 minutes or until potatoes are tender; do not drain.
Meanwhile, in a saucepan over low heat, heat milk with cheese until
cheese has melted, stirring often. Do not allow cheese mixture to boil!
Add shrimp to potatoes and cook until they are pink and tender. About 3 minutes.
To serve, add hot cheese mixture. Heat but do not boil.