Preheat the oven to 350°F (175°C) and grease a 9×13-inch baking dish.
In a large bowl, combine hashbrowns, diced onion, bell pepper, and cooked sausage. Stir until well mixed.
In a separate bowl, whisk together eggs, milk, salt, and pepper until smooth.
Pour the egg mixture over the hashbrown mixture and stir to combine.
Transfer the mixture into the prepared baking dish and spread it evenly.
Sprinkle shredded cheddar cheese evenly over the top.
Bake for 45–50 minutes, or until the top is golden brown and the center is set.
Let it cool for a few minutes before slicing and serving warm.
