A delicious and hearty make ahead sausage hashbrown casserole that combines savory sausage, crispy hashbrowns, and creamy cheese into a comforting bake perfect for busy mornings or leisurely brunches.
In a large skillet over medium heat, cook the ground sausage until browned and cooked through, breaking it apart with a wooden spoon. This should take about 6-8 minutes; drain excess grease if necessary.
Stir in the diced onion and bell pepper (if using) into the skillet with the sausage. Sauté for an additional 3-4 minutes until the vegetables are tender.
In a large mixing bowl, combine the thawed hashbrowns, cooked sausage mixture, cheddar cheese, mozzarella cheese, garlic powder, salt, and black pepper. Mix until evenly combined.
In a separate bowl, whisk together the eggs and milk until smooth.
Grease a 9x13-inch baking dish. Spread the hashbrown mixture evenly in the dish, pressing down slightly for an even layer. Pour the egg mixture evenly over the top.
Optional: Add additional cheese and chopped green onions on top.
Bake in the preheated oven for 40-45 minutes until the casserole is set and the top is golden brown.