Mix the oatmeal, milk, and 4 cups of water in a large, deep saucepan and bring to a boil over medium high heat. When it boils, quickly lower heat to very low. Stir in brown sugar, dried cranberries, flaxseed meal, sunflower seeds and salt. Cook at a low simmer for 15-20 minutes, or until very thick and creamy.
Stir often to prevent burning.
Serve with additional milk and sprinkle with a tablespoon of the Grape nuts cereal if desired, or cool and refrigerate to reheat later in the week.