Heat 2-3 tablespoons oil in a skillet over medium heat; add in onion and saute for about 6-8 minutes or until tender (if adding in garlic add in the last 2-3 minutes of cooking).
In a bowl mix the thawed hash browns with onion, seasoned salt and pepper.
Heat more oil in the skillet; drop the hash brown mixture into about 3-inch rounds (if you find that the mixture has problems holding together then add in an slightly beaten egg).
Cook about 4-5 minutes per side, or until lightly browned and crispy (press down with a spatula to flatten).
Top each potato round with a slice of cheese; cook until melted.