Step 1

Whisk together the eggs, milk, salt and pepper in a large bowl.

Step 2

Spray the insert of a large (5-quart or 6-quart size) slow cooker with nonstick spray. Layer one-third of the thawed hash browns in the bottom. Top with one-third of the ham, one-third of the onion and one-third of the shredded cheese. Repeat these layers two times. Editor's Tip: Save time by using frozen diced onions instead of chopping your own. Look for them in the frozen veggie case at the store.

Step 3

Pour the egg mixture into the slow cooker over the top of the layered ingredients. Cover the insert, and slide it into the fridge to rest overnight.

Step 4

Transfer the insert to the slow cooker base. Cover and cook on low for four to five hours, until the casserole is set and beginning to brown at the edges. Turn off the slow cooker, and remove the insert to a trivet or cooling rack. Uncover and let the casserole stand for 30 minutes.