Make-Ahead Breakfast Casserole with Sausage, Eggs and Cheddar

How to Make Make-Ahead Breakfast Casserole with Sausage, Eggs and Cheddar

1. 1

   Step 1: Cook the sausage and onion

   Heat a large skillet over medium heat and add the ground breakfast sausage. Break the meat into crumbles and cook until mostly browned, then add the diced onion and continue to cook until the sausage is fully cooked and the onion is softened and translucent, about 6–8 minutes. Drain any excess fat, then transfer the mixture to a bowl and set aside to cool slightly.

   For this step

   • 1 lbground breakfast sausage
   • 1 cupyellow onion, diced
   
2. 2

   Step 2: Prepare the baking dish and bread

   Preheat the oven to 350°F (175°C) if baking immediately; if making ahead, skip preheating and refrigerate assembled casserole. Grease a 9x13-inch (23x33 cm) baking dish with the butter, then spread the cubed day-old bread in an even layer across the dish. Gently press the bread so pieces nestle together but still leave some air pockets for the custard to soak in.

   For this step

   • 1 tbspunsalted butter (for greasing)
   • 6 cupsday-old bread, cut into 1-inch cubes (white or sourdough)
   
3. 3

   Step 3: Whisk the egg custard

   In a large bowl, whisk together the eggs, whole milk, kosher salt and black pepper until smooth and slightly frothy. Let the mixture sit for a minute so bubbles subside; this ensures an even custard that soaks into the bread.

   For this step

   • 8 largelarge eggs
   • 2 cupswhole milk
   • 1 tspkosher salt
   • 3/4 tspfreshly ground black pepper
   
4. 4

   Step 4: Assemble the casserole

   Scatter half of the shredded cheddar over the bread, then spread the cooked sausage and onion evenly on top. Pour the egg mixture slowly over the layers, pressing the bread down gently with a spatula so the custard is absorbed. Sprinkle the remaining cheddar evenly across the surface.

   For this step

   • 2 cupssharp cheddar, shredded
   
5. 5

   Step 5: Chill (make-ahead) or bake

   For make-ahead: cover tightly with plastic wrap and refrigerate for at least 6 hours or up to 24 hours to allow flavors to meld and the custard to fully soak the bread. To bake immediately or after chilling: remove plastic, let sit at room temperature 15 minutes, then bake uncovered at 350°F (175°C) for 40–45 minutes until the center is set and the top is golden brown. A knife inserted in the center should come out mostly clean.
6. 6

   Step 6: Rest and serve

   Allow the casserole to rest 10 minutes before slicing; this helps it set and makes cleaner portions. Serve warm, garnished with chopped fresh herbs or sliced green onions if desired; leftovers keep 3–4 days refrigerated and reheat well.

1. Heat a large skillet over medium heat and add the ground breakfast sausage. Break the meat into crumbles and cook until mostly browned, then add the diced onion and continue to cook until the sausage is fully cooked and the onion is softened and translucent, about 6–8 minutes. Drain any excess fat, then transfer the mixture to a bowl and set aside to cool slightly.
2. Preheat the oven to 350°F (175°C) if baking immediately; if making ahead, skip preheating and refrigerate assembled casserole. Grease a 9x13-inch (23x33 cm) baking dish with the butter, then spread the cubed day-old bread in an even layer across the dish. Gently press the bread so pieces nestle together but still leave some air pockets for the custard to soak in.
3. In a large bowl, whisk together the eggs, whole milk, kosher salt and black pepper until smooth and slightly frothy. Let the mixture sit for a minute so bubbles subside; this ensures an even custard that soaks into the bread.
4. Scatter half of the shredded cheddar over the bread, then spread the cooked sausage and onion evenly on top. Pour the egg mixture slowly over the layers, pressing the bread down gently with a spatula so the custard is absorbed. Sprinkle the remaining cheddar evenly across the surface.
5. For make-ahead: cover tightly with plastic wrap and refrigerate for at least 6 hours or up to 24 hours to allow flavors to meld and the custard to fully soak the bread. To bake immediately or after chilling: remove plastic, let sit at room temperature 15 minutes, then bake uncovered at 350°F (175°C) for 40–45 minutes until the center is set and the top is golden brown. A knife inserted in the center should come out mostly clean.
6. Allow the casserole to rest 10 minutes before slicing; this helps it set and makes cleaner portions. Serve warm, garnished with chopped fresh herbs or sliced green onions if desired; leftovers keep 3–4 days refrigerated and reheat well.