Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish.

Spread the crumbled and cooked breakfast sausage evenly in the bottom of the prepared baking dish.

Place the bread cubes over the sausage layer, followed by the shredded cheddar cheese.

In a bowl, whisk together eggs, whole milk, Dijon mustard, salt, black pepper, and ground nutmeg (if using).

Pour the egg mixture over the sausage, bread, and cheese layers in the baking dish.

Drizzle melted butter over the top for a golden finish.

Allow the casserole to sit for about 15 minutes, allowing the bread to absorb the egg mixture.

Bake in the preheated oven for 45-50 minutes or until the center is set and the top is golden brown.

Remove the Classic Sausage and Egg Casserole from the oven and let it cool for a few minutes.

Optionally, garnish with fresh parsley before serving.

Slice and serve the casserole warm, enjoying the classic combination of savory sausage, fluffy eggs, and cheesy goodness. Delight in this comforting breakfast casserole for a hearty morning meal!