This breakfast casserole is adaptable to whatever ingredients you have on hand—cheese, veggies, meats—and can be assembled the night before and baked in the morning. Or eaten for dinner—your choice!

Photography Credit: Elise Bauer

On vacation, having too much fun to realize that nothing has been planned for meals, fridge mostly empty, remembering that uh-oh, I’m the one in charge of feeding my friend’s children that day.

Oops!

Open the refrigerator door, see half a dozen eggs, half a carton of milk, some cheddar cheese, leftover sausage from biscuits and gravy the day before, a little broccoli, a leftover ear of corn (cooked).

Open the freezer and see half a loaf of sliced bread. Saved!

Whew. I won’t have to reach for the boxed mac and cheese.

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What is a breakfast casserole?

Have you ever made a breakfast casserole?

The basic ingredients are eggs, cheese, milk, and bread. It’s the easiest thing in the world to put together. We have a sausage breakfast casserole on the site that is one of my favorites.

The great thing about a breakfast casserole is that you can add almost anything you want to the base. Italian sausage is my all-time favorite, but bacon or ham will do, too. Or make it veggie, with zucchini, broccoli, basil, and onions.

The first time I served this to the kids they insisted that it had to go on the website. The name they picked was “Open Fridge Breakfast Bake” because basically that’s what I did—opened the fridge, put everything I could find into a casserole dish, and baked it.

How to Make a Breakfast Casserole

To make a breakfast casserole you beat some eggs, add milk and cheese, add cubed bread, add “mix-ins” like mushrooms, veggies, sausage, and herbs, put it in a casserole dish and bake.

Easy, right? The ingredients basically all come together in one big casserole pan, but there are a few steps I would recommend first:

If you are using a lot of mushrooms, sauté them a bit beforehand to release some of their moisture.

You can add cooked, sturdy veggies such as broccoli into the casserole, or put them in raw. If using raw veggies, cut them into smaller pieces and know that they’ll be crunchier if you put them in raw instead of cooked.

If you are adding sausage or bacon, cook it first before adding it to the casserole.

The proportions of ingredients are adjustable. If you add more eggs, it will result in a casserole that is more firm and less likely to deflate.

Day-old or stale bread works best for a breakfast casserole, but if you don’t have any, just leave slices of fresh bread out on the counter to dry for a few hours, or put the slices in a low oven (200°F, 10 min) or toaster for a minute (just enough to dry them a little).

What to Serve With a Breakfast Casserole

Breakfast casserole is truly a meal in itself! It has starch (bread), milk, cheese, meat, and vegetables. It can be made for breakfast, lunch, or dinner.

Serve it with some sliced fresh fruit on the side for breakfast, or if making for dinner, a green salad. If you omit the veggies in the casserole, consider serving some sautéed vegetables on the side. Or if leaving out the meat, some crispy bacon or cooked sausages.

Make Ahead Instructions

Breakfast casseroles are almost designed to be made ahead. You can assemble the whole thing the night before, put it in the fridge (covered), and bake it the next morning. It’s minimal work when you wake up and a low stress breakfast if you have a group of people to feed.

How to Keep and Reheat a Breakfast Casserole

This breakfast casserole will keep for a few days in the fridge, covered. You can microwave it until it’s hot, one serving at a time, or you can reheat the whole casserole in a 350°F oven for 15 to 20 minutes until it’s heated through.

Do you have a favorite breakfast casserole combo? If so, please let us know about it in the comments.

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