This baked egg casserole with spinach and mushrooms is a healthier alternative to sweet breakfast dessert casseroles like my ultimate blueberry breakfast bake. Savory and oh-so-good, the combined sausage, cream of mushroom soup, spinach, mushrooms and cheese really make this breakfast recipe taste delicious enough for dinner.
With all the savory and sweet breakfast casseroles out there that smash in the carb loaded hash browns or the sweet French toast, I wanted to add little more savory experience for holiday mornings. This breakfast casserole, which is fully loaded with cheese, spinach, and mushrooms, is a great egg bake recipe that anyone that loves these veggies will truly enjoy. In fact, one of my readers said “THIS WAS SO GOOD” and I hope you feel the same way!
Breakfast Egg Casserole with Spinach
Before you get started on this casserole, please know there is some pre-prep work – cook and drain pork sausage first and then the recipe is ready to be assembled. This breakfast casserole (like most) takes about 55-60 minutes to cook, therefore cooking times need to be planned ahead.
Breakfast Casserole Ingredients
- 10 ounces seasoned croutons
- 1lb ground pork sausage, cooked and crumbled
- 6 large eggs
- 2-1/4 cups milk
- 1 can, 10.5 oz. cream of mushroom soup
- 1 package, 10 oz. frozen spinach, thawed
- 8 oz. sliced fresh mushrooms
- 2 cups shredded cheese – Monterey jack or Cheddar Jack
- salt and black pepper
Overnight Egg Bake Recipe Questions
Does this casserole recipe with spinach have to be made the night before? No, but it CAN be prepped overnight. Please see recipe card for the instructions.
Does the spinach need to be drained of excess moisture? Nope! Do not drain thawed spinach, or squeeze any water out of it. Some recipes (like spinach dip) require that but this breakfast bake does not.
Can I make breakfast casserole ahead of time and can this baked egg casserole be made ahead? Yes and yes! Many breakfast casseroles are set up to easily be prepped ahead of time and this one is no exception. Simply prep your entire casserole, cover well with foil, and place in fridge till baking the next day. Remove foil prior to baking. As with all make ahead recipes, the recipe may take a bit longer in the oven as the recipe has to come up from very cold ingredients to cooking temp before bakes.
Is this spinach egg bake the same as a spinach casserole? No, If you are looking for spinach casserole side dish, its very different.
Can pork sausage be substituted for other proteins? If you do not like breakfast sausage, feel free to use hamburger beef.
Are there any other cheese alternatives? Cheese is something that can be really specific for people but no worries – any shredded cheese (cheddar cheese, Monterey Jack, Pepper Jack, Cheddar Jack) all work great.
What other ingredients can go in a breakfast casserole? This spinach mushroom casserole is really specific in flavoring, so I personally do not choose to add much to it, although if you are an onion person, a half cup of diced onions would go just fine. Just put in with the spinach mixture (at the same time) before dumping onto sausage.
Easy Spinach Breakfast Casserole Recipe
Grease a 9×13 baking dish with nonstick cooking spray.
Spread croutons into the bottom of the pan.
Sprinkle cooked and crumbled sausage on top of croutons.
In a large bowl, add eggs, milk and cream of mushroom soup and whisk eggs well.
Fold in thawed but not drained spinach and sliced mushrooms.
Mix all ingredients together well.
Add shredded cheese and mix again.
Pour spinach and egg mixture on top of croutons and sausage in the baking dish.
Bake spinach casserole at 325 for 50-55 minutes (see note about timing for overnight casserole).
Remove dish from oven.
Let casserole stand for 5 minutes before slicing and serving.
Serves approximately 12 slices.
As a side note, you may notice two kinds of images in this recipe (one clear casserole dish and one blue one). This is because we made it two separate times and updated the images to best show you the step.
Your changes and feedback are always welcome and we love if you leave comments on your own alterations so we can try them as well.
~Trisha & Char