Back Country Mojakka (Finnish Fish Stew)

In a large camping Dutch oven, bring water, onions, and salt to boil over a fire (or a regular Dutch oven on the stovetop). Add dried hash browns. Cover and set on the side of the fire (or off the burner) for 10 minutes. Slowly stir in dried milk; return to heat and bring mixture to a boil. Add as many boneless, skinless fish fillets cut in 1 inch squares as desired plus optional margarine. Cover and remove from heat. Add salt and pepper to taste.