Begin by preheating your oven to 350°F (175°C) to ensure it's ready for baking when your casserole is assembled.

Crumble the ground sausage into a skillet and cook over medium heat, stirring frequently and breaking it apart with a spatula until it is fully browned. Remove the skillet from the heat once the sausage is cooked through.

In a large bowl, whisk together the eggs and milk until fully combined and slightly frothy. Add salt and black pepper, then stir well. I like to make sure the eggs are thoroughly beaten for a fluffier casserole.

Add the frozen hash brown potatoes, browned sausage from Step 2, and shredded cheddar cheese to a lightly greased 9x13-inch baking dish. Stir them together until evenly combined. Pour the egg mixture from Step 3 evenly over the top. Give the dish a gentle stir to help distribute ingredients if needed.

Cover the casserole dish with foil and bake at 350°F for 45 minutes. Then, remove the foil and continue to bake for an additional 10-15 minutes, or until the casserole is bubbly and the cheese is fully melted on top. Allow to cool for a few moments before serving. For an even more golden and delicious top, I like to turn on the broiler for 1-2 minutes at the end, keeping a close eye so it doesn’t burn.