The oatmeal will continue to thicken as it cools. If you prefer a looser consistency, thin the oatmeal with boiling water. Customize your oatmeal with toppings such as brown sugar, toasted nuts, maple syrup, or dried fruit like strawberries, blueberries, and bananas.
Bring 3 cups water to boil in large saucepan over high heat. Remove pan from heat; stir in oats and salt. Cover pan and let stand overnight.
Stir remaining 1 cup water into oats and bring to boil over medium-high heat. Reduce heat to medium and cook, stirring occasionally, until oats are softened but still retain some chew and mixture thickens and resembles warm pudding, 4 to 6 minutes. Remove pan from heat and let stand for 5 minutes. Stir and serve, passing desired toppings separately.
