Begin by thawing the frozen shredded hash browns in the refrigerator overnight or using the microwave. Preheat your oven to 375°F (190°C) while you grease a 9x13-inch baking dish with cooking spray or butter.

In a large skillet over medium heat, brown the beef breakfast sausage and diced bacon for approximately 5-7 minutes. Drain excess grease, then add the diced bell peppers and spinach, sautéing for an additional 3-5 minutes until the veggies are tender.

Press the thawed hash browns evenly into the bottom of the greased baking dish.

In a large mixing bowl, whisk together the eggs, whole milk, cream cheese, and sour cream until smooth. Stir in the ranch seasoning mix, onion powder, garlic powder, salt, and black pepper.

Layer the cooked sausage, bacon, sautéed bell peppers, and spinach over the pressed hash browns. Sprinkle shredded cheddar cheese on top.

Pour the prepared egg mixture over the layered ingredients, ensuring it is evenly distributed. Top with remaining cheddar cheese.

Cover the baking dish with foil and bake for 30 minutes. Remove the foil and continue baking for 25-35 minutes until the edges are golden brown and the center has set.

Once baked, remove the casserole and let it rest for 10-15 minutes before serving.