Bring all ingredients except the oats to a boil. Turn heat to low and stir in 4.5 cups rolled oats. Cook for about 5 minutes until the water is absorbed. Don't overcook. If it is too soupy, add some oats at about 5 minutes and cook for only a few more minutes until thickened. Fill a rectangular non-stick baking pan with the mixture (makes square patties, easier than forming little circles). The pan could be anywhere from 9 x 46 cm (22.5 X 45 cm.), 30 cm (30 cm.) square or larger to make patties about a half-inch (1.3 cm.) thick. If too thin they'll be tough and will dry out. Total cooking time is 45 minutes. Bake at 180ºC . for 25 minutes. Then use a utensil that won't scratch your pan to cut the giant burger into 9 cm to 10 cm (10 cm.) square burgers and flip them over. Cook another 20 minutes. Serve in buns or as a main course, hot or cold. Can be frozen.