Preheat the oven to 350 degrees. Grease a 9x13 baking dish, set aside.
Cook the sausage and bell peppers until the meat is cooked through and the peppers are softened.
2 pounds ground pork breakfast sausage, 1 cup bell pepper
Add the green onions, mix and remove to a paper towel-lined plate.
1 cup green onions
In a large bowl whisk the eggs, half and half, salt, pepper, and ground mustard. Add in the hash browns, 2 cups pepper jack cheese, and sausage mixture.
10 large eggs, 1 cup half and half, 1 teaspoon kosher salt, 1/2 teaspoon freshly ground black pepper, 1 teaspoon ground mustard, 5 cups frozen hash browns, 3 cups pepper jack cheese
Transfer to baking dish and sprinkle the remaining 1 cup of cheese evenly over the top.
Bake at 350 degrees for 55-60 minutes.
Or cover and refrigerate overnight. The next morning remove the baking dish from the refrigerator at least 1 hour before baking, follow baking instructions.