Heat oven to 350°F.
Spray a 13 x 9-inch baking dish with no-stick cooking spray.
Heat water, butter, garlic salt and onion salt to boiling in a 6-quart Dutch oven or saucepan. Remove from heat. Add cream cheese, milk and sour cream, stirring until cream cheese is dissolved.
Stir in potato flakes, mixing until all ingredients are well combined. Spread mashed potato mixture into prepared pan.
Sprinkle with paprika and bake 1 hour or until bubbling around edges and golden brown. NOTE—To make this dish ahead: Before adding paprika and baking, cover the potato mixture and store in the refrigerator for up to 48 hours. When ready to bake, sprinkle
Top with chopped bacon and parsley, if desired.
Variation: To make with Pet Evaporated Milk: Heat 7 1/2 cups water with butter, garlic salt, and onion salt. Replace 2 cups milk with 1 (12 ounce) can Pet Evaporated Milk.