Preheat & Prep: Preheat the oven to 350°F (175°C) and lightly grease a baking dish with non-stick spray or olive oil.
Whisk the Eggs: In a large bowl, whisk together the eggs, milk, salt, and pepper until fully combined and slightly frothy.
Add the Flavor: Stir in shredded cheddar cheese, diced green onion, and your choice of cooked bacon, sausage, or ham.
Bake to Perfection: Pour the mixture into the prepared baking dish and bake for 20-25 minutes, or until the eggs are set and slightly golden on top.
Slice & Serve: Let cool slightly before slicing into squares. Serve warm and enjoy!