Easy Make-Ahead Breakfast Casserole Recipe

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Hi Bold Bakers!

WHY YOU’LL LOVE THIS RECIPE: An ideal weekend brunch starts without stress from this Easy Make-Ahead Breakfast Casserole recipe made with sharp cheddar, savory sausage, and mildly sweet spinach. 

Weekends should be lazy, but they should also feature plenty of delicious food. That’s why my family and I are currently obsessed with this Easy Make-Ahead Breakfast Casserole Recipe!  

The timing of this casserole works great for me. I love that I can assemble it the night before, pop it in the refrigerator, and then bake it off in the morning right after I hit brew on our coffee pot. 

But I also love that it’s easy and quick enough that if I’m too exhausted to think of it the night before, I can quickly assemble it in the morning, too! It’s a really excellent no-fuss breakfast — just get it ready when you have the energy. 

I like to make this Easy Make-Ahead Breakfast Casserole Recipe with cooked uncased ground sausage, spread throughout so there is a nice salty, savory morsel in every bite, sharp cheddar cheese, and defrosted and drained frozen spinach. You can use any cubed stale bread you have on hand, but if it’s been a week of baking for us, I love using my leftover No Knead Whole Wheat Bread or White Sandwich Bread that has gone stale before we were able to use it. 

Table Of Contents

• What Is Breakfast Casserole?
• Tools You Need
• Easy Make-Ahead Breakfast Casserole Recipe Ingredients
• How To Make Easy Make-Ahead Breakfast Casserole 
• How Do I Store Leftover Breakfast Casserole?
• Can You Freeze Breakfast Casserole?
• FAQs
• Gemma’s Pro Chef Tips
• More Easy Breakfast Recipes

What Is Breakfast Casserole?

Breakfast casserole is a bit of a catch-all name, but the recipe is always typically the same. It’s a casserole made with eggs, milk, and cheese.

While this Easy Make-Ahead Breakfast Casserole calls for sausage, cheddar, and spinach, you can substitute any protein, any cheese, and any vegetable that you prefer! 

I also use stale bread in my Breakfast Casserole. I hate to throw away perfectly good food, and it’s a lot more filling.

Tools You Need

• Measuring cups and spoons
• Mixing bowls
• 9 x 13-inch (23 x 33 cm) casserole dish
• Chopping board
• Chopping knife
• Carving knife
• spatula
• Frying pan
• Grater

Easy Make-Ahead Breakfast Casserole Recipe Ingredients

• Eggs: You need a full dozen of eggs for this recipe. I use large eggs.
• Whole milk and heavy cream: The combination of whole milk and heavy cream keeps this breakfast feeling light, creamy, and delicious.
• Ground sausage: I like to use uncased ground sausage because I like pieces of meat throughout. You can also use diced ham or bacon.
• Sharp cheddar cheese: Use whatever shredded cheese you prefer, but for a simple breakfast, I like to use cheddar.
• Frozen spinach: Frozen vegetables are super convenient and tasty. They’re packed at peak freshness, so you never have to worry. Be sure to thaw and drain your spinach before using. 
• Onion and garlic: What’s a savory dish without onions and garlic?
• Salt and pepper
• Cubed, stale bread: Any type of bread will do, but be sure to use stale bread, so it holds its texture with the wet ingredients! No stale bread? See my note below. 

How To Make Easy Savory Make-Ahead Breakfast Casserole

1. Whisk eggs, milk, and cream until well beaten. Stir in the sausage, cheese, spinach, onion, garlic, salt, and pepper.
2. Stir the bread cubes into the liquid until well coated, and transfer the mixture to your baking dish. Allow this egg mixture to sit for at least 30 minutes. 
3. If you are making it the day off, bake for about 45 minutes in a preheated 375°F (190°C) oven. If you are making it the following day, keep it covered in the fridge overnight, and allow it to come to room temperature for 20 minutes before baking. 
4. Let the baked dish rest for 10 minutes before serving. (Top with fresh avocado slices for more fiber!) 

How To Store Leftover Breakfast Casserole

You can store leftover breakfast casserole for up to 3 days, covered, in the refrigerator. To reheat, bake in a preheated 300°F (150°C) oven for 15 minutes, or warm up in the microwave. 

How To Freeze Breakfast Casserole

Yes, you can freeze baked breakfast casserole for up to 2 months. I suggest baking it in a disposable aluminum pan and covering it well with foil before freezing. 

FAQs

How far in advance can I make breakfast casserole?

You can make this easy breakfast casserole up to 24 hours in advance. In fact, allowing the flavors to develop together will make it even tastier! Be sure to keep it in the fridge until 20 minutes before you are ready to bake. 

Can you make this recipe vegetarian? 

You can make this Breakfast Casserole vegetarian by removing the sausage. You can use either your favorite meat alternative (even cooked potatoes or hash browns!) or add more cooked vegetables such as broccoli, mushrooms, bell peppers, or other favorite veggies!

Gemma’s Pro Chef Tips

• You can vary this recipe by swapping the spinach for a different vegetable. Be sure to cook, steam, or saute your vegetables first; otherwise, your casserole will be too watery.
• Switch up cheddar cheese for Gruyere, Swiss Cheese (for less sodium), or Monterey Jack in the same amount. Add Pepper Jack Cheese for the heat if you prefer. You can also use feta or bleu cheese, but reduce the amount in half, as they are very moist.
• Try making this with the most faved No Knead Whole Wheat Bread or White Sandwich Bread!

More Easy Breakfast Recipes

• How to Make Quiche
• Cinnabon Cinnamon Rolls
• Authentic Irish Potato Farls
• Georgie’s Healthy Breakfast Muffins
• Complete Breakfast Muffins

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Georgie's Healthy Breakfast Muffins