You can prep this the day ahead. Make the complete recipe without baking it. Put the mixture in your 9x13 baking dish or large 12" oven safe skillet and allow the mixture to cool, then chill in the fridge for up to 10 hours. The next morning, remove the casserole from the frdige and let it warm up a bit to room temperature, about 25 minutes. You can do this while the oven pre-heats. BEWARE: If you're pre-cooking it in a cast iron pan might turn the potato mixture gray, which happend to a some readers. We suggest using a pan that isn't cast iron. NOTE: Not all shredded hash browns are created equal. Some are more firm while others are mushy. Ore Ida refrigerated shredded hash browns are very mushy. If you want your hash browns crispy, then we suggest using extra oil to fry the hash browns or buy the crispy pre-cooked patties.
1/2pound(227g)uncooked Sausage, removed from casings if needed
20ounce(567g)package refridgerated Hash Browns
1Red Bell Pepper, diced
(optional toppings) chopped green onions or chopped parsley
Heat oven 375° F. Grease 9"x13" baking dish *see head note (skip this if cooking in an oven-safe skillet) and set aside.
In large bowl beat the eggs, milk, sour cream, salt, and pepper together. Add 2.5 cups of the cheese and stir until everything is combined (remaining 1/2 cup of cheese is for topping). Set aside.
Heat large 12" skillet on medium-high heat, cook bacon until browned. Add onions and garlic, cook until soft, about 1 minute. Add sausage and cook until browned and cooked, about 5 minutes. Break apart sausage into small chunks as you cook it.After sausage is browned, add the hash browns and red bell peppers. Cook mixture for about 5 minutes or until the potatoes are slightly brown.
Combine the sausage/potato mixture and the egg mixture mix together. Pour mixture into 9"x13" baking dish *unless using oven-safe skillet-see head note. Top with remaining 1/2 cup of cheese.
Cover the casserole dish with foil. Bake for 35 minutes. Remove the foil and bake uncovered for about another 25 minutes or until casserole is cooked through and cheese is melted. If the casserole is not cooked through all the way, give it a gentle stir and bake un-covered for another 10 minutes.Add optional green onion or minced parsley topping. (Please try to use a 9"x13" baking dish or large 12" oven safe skillet. If you are using a smaller baking dish or skillet, the mixture will be thicker and won't cook through the middle. You might have to stir it in the middle half way during cooking to ensure it cooks all the way)