Add cheese, mushroom, and eggs to hash brown cups and return the muffin tin to the oven for another 20-25 minutes. Remove from oven and let cool slightly before serving. A light sprinkle of salt ...
Spread the thawed hash browns evenly in the greased baking dish. Layer the cooked sausage on top. Spread diced bell pepper and chopped onion over the sausage. Sprinkle ½ cup of cheese over the top.
Add the egg, a good couple of pinches of salt and freshly ground black pepper (you need to salt the mixture well otherwise the hash browns can be quite bland). Mix the ingredients well.