Preheat your oven to 400 degrees. Prepare a 12 cup muffin pan with cooking spray and set aside.
In a large sized bowl beat 1 egg. Next add hash browns, olive oil, 1 cup shredded cheese and ½ teaspoon of salt and of pepper. Stir until blended.
Divide mixture as equally as possible into each muffin cup. Try to fill each cup as evenly as possible. Press potato mixture down as much as you can.
Bake for about 15 minutes or until potatoes start to crisp up. Remove hash browns from your oven and set aside on your stove top. Leave your oven on.
While the hash browns are baking, combine eggs and milk or cream in a large bowl.
Add a pinch of cheese to each muffin cup, on top of your baked hash browns.
Next add a pinch of cooked bacon, ham or sausage, peppers and onions, on top of the cheese.
Pour your egg mixture evenly into each muffin cup. Sprinkle with salt and pepper if desired.
Bake for between 10 and 15 more minutes or until eggs are cooked and a toothpick inserted comes out clean. Allow muffins to cool in the tin for about 5 more minutes before serving. Enjoy!