01 -
Grease a 6-quart slow cooker with butter or nonstick spray.
02 -
Spread half of the frozen hash browns evenly in the bottom of the slow cooker.
03 -
Scatter half of the cooked sausage and half of the shredded cheddar cheese over the hash browns.
04 -
Layer the remaining hash browns, sausage, and cheddar cheese in the same order.
05 -
In a large bowl, whisk together eggs, milk, sour cream (if using), garlic powder, salt, and black pepper until fully blended.
06 -
Pour the egg mixture evenly over the layered ingredients in the slow cooker. Gently press down to ensure absorption.
07 -
Cover and cook on LOW for 7 to 8 hours or on HIGH for 3 to 4 hours until the center is set.
08 -
Allow the casserole to rest for 10 minutes before slicing. Serve warm.