📖 Instructions

1. Prep the oven and baking dish: Start by preheating your oven to a comfortable 375°F (190°C). This ensures it's perfectly hot when your casserole is ready to go in. Take your trusty 9x13 inch baking dish and give it a good spray with cooking spray; we don't want anything sticking!
2. Cook the sausage: Grab a large skillet and place it over medium-high heat. Crumble your ground breakfast sausage into the hot pan. Cook it, breaking it up with a spatula, until it's beautifully browned all over. This usually takes about 5-7 minutes. Once it's done, drain any excess grease – nobody wants a greasy casserole, right? Set the cooked sausage aside to cool slightly.
3. Prepare the bread: Take about 6 slices of your chosen bread (stale bread works great here, but fresh is fine too!). Tear or cut them into rough 1-inch cubes. You want them to be bite-sized. Scatter these bread cubes evenly across the bottom of your prepared baking dish.
4. Layer the sausage and cheese: Now, sprinkle that lovely cooked sausage evenly over the bread cubes in the baking dish. After the sausage, generously scatter 1 cup of shredded cheddar cheese over the sausage and bread. This creates a fantastic cheesy layer throughout.
5. Whisk the egg mixture: In a large mixing bowl, crack open your 12 large eggs. Pour in 2 cups of whole milk and add a pinch of salt (about 1/2 teaspoon) and a good grind of black pepper (1/4 teaspoon). Use a whisk to beat everything together thoroughly until the egg yolks and whites are completely combined and the mixture is nice and uniform. You're aiming for a light, frothy consistency that promises those pillowy eggs.
6. Pour and moisten: Carefully pour the egg and milk mixture evenly over the bread, sausage, and cheese in the baking dish. Make sure all the bread cubes get nicely soaked; you might need to gently press them down with the back of a spatula to ensure they absorb the liquid. This is key for that soft, pillowy texture.
7. Top with more cheese: For that golden-brown, irresistible crust, sprinkle the remaining 1/2 cup of shredded cheddar cheese over the top of the casserole.
8. Chill (optional but recommended for make-ahead): If you're making this ahead of time (and I highly recommend it!), cover the baking dish tightly with aluminum foil or plastic wrap and pop it in the refrigerator for at least 4 hours, or even better, overnight. Letting it chill allows the bread to fully absorb the egg mixture, leading to an even more cohesive and tender casserole. If you're baking it right away, proceed to the next step.
9. Bake the casserole: Place the baking dish into your preheated oven. Bake for 45-55 minutes. You're looking for a beautiful golden-brown top, and when you gently jiggle the dish, the center should be set, not wobbly. To double-check, a knife inserted into the center should come out clean. If the top starts browning too quickly, you can loosely tent it with aluminum foil for the last 10-15 minutes of baking.
10. Rest and serve: Once baked, carefully remove the casserole from the oven. Let it rest for 5-10 minutes before slicing and serving. This resting period allows the casserole to set further, making for cleaner slices and a better overall texture. Serve warm and watch it disappear!