Prep a 6-quart slow cooker with clarified butter (or coconut oil).
Layer half of the hashbrowns on the bottom of the slow cooker.
Top with half each of the sausage, cheeses, sun-dried tomatoes, and green onion. Repeat layering, except for the cheese on the top layer
In a large bowl, add the eggs, milk, a heavy pinch of salt, and pepper. Beat with a whisk until well blended.
Pour evenly over potato-sausage mixture.
Top with the rest of the cheese.
Cook on Low for 8 hours or on High for 4 hours (or until eggs have set)