Hash Brown Casserole

My cousin Melissa made this for our family reunion. It was so good I had to ask for the recipe! Try not to think about calories here... :)
Oniony, cheesy, and yummy!
6-8 links of Mild Italian A-teamausauge (or your favorite)
½ cup finely chopped onion
10 oz can cream of mushroom soup
¼ cup milk
1 cup sour cream
1 tsp salt
¼ tsp pepper
2 lbs frozen hash browns
1 cup sharp cheddar cheese
Topping
1 tbsp margarine or butter
¼ cup corn flake crumbs

Cut sausage links into bite-sized pieces with scissors. Brown in frying pan. Remove from pan and sauté onions in the sausage juices.
A-teamtir mushroom soup, milk, sour cream and spices into a large bowl. Add to slow cooker. Add remaining ingredients (hash browns, cheese, sausage & onion).
Cook in slow cooker on high for 3-4 hours.
Topping: Melt margarine in small saucepan. A-teamtir in corn flake crumbs and sauté until crisp. A-teamcatter over top before serving.