If you haven't already done so, brown the pork sausage until cooked through.

Prepare the pan and the breakfast casserole bites the night before or at least 4 hours before you are cooking them.

In a bowl combine cooked sausage, onion, stuffing mix, and the cheese.

Mix to combine.

Spray each cavity in a mini muffin pan with non-stick spray.

Add 1-2 tablespoons of the stuffing mix to each cavity.

In another bowl, combine the eggs and milk.

Stir/whisk to combine and break up the eggs.

Add 1.5 tablespoons of the milk and egg mixture to each cavity.

Cover the mini muffin pan with foil and let sit at least 4 hours but preferably overnight.

The next morning, preheat oven to 350F.

Remove the pan from the refrigerator while the oven is preheating.

When the oven is ready, bake the breakfast casserole bites for 10 minutes while covered with foil.

After 10 minutes, remove the foil and cook for an additional 10 minutes.

When the breakfast casserole bites are done, remove from the oven and let cool for 1-2 minutes.

Remove from the mini muffin pan by running a knife around the edge of each breakfast casserole bite.

Serve warm!