Spinach, Mushroom and Cheese Breakfast Casserole

Warm up your holiday with an easy, make ahead breakfast that is guaranteed to keep spirits bright. This Spinach, Mushroom and Cheese Breakfast Casserole is filled with cozy comfort. Studded with toasted cubes of rustic bread, it’s a stunning, cheesy, crunchy topped crowd pleaser.  

I used canned evaporated milk in place of the half-and-half to make this a bit healthier. You could add sausage, bacon, or ham, but it is truly delicious as is. I only used 6 cups of bread, relying on what I had on hand and making up the difference with some of the sourdough bread that I keep churning out. No spinach? Use kale. Sliced button mushrooms, also okay. Fill in the blanks with what you have. This is a wonderful, forgiving recipe. One you will make again and again. 

Make this the night ahead and write the temperature and cooking time on the wrap with a Sharpie, ready to go for the morning. Reheat leftovers by microwaving at 1/2 power until warmed through. 

Wishing you a safe, healthy, joy-filled holiday.

Spinach, Mushroom and Cheese Breakfast Casserole

  • 4 Tablespoons extra-virgin olive oil
  • 8 cups rustic Italian bread, crust removed, cut into 1-inch cubes
  • Kosher salt and freshly ground black pepper
  • 10 ounces cremini mushrooms, sliced (about 4 cups)
  • 2 cloves garlic, minced
  • 5 ounces fresh baby spinach (about 5 cups)
  • 4 ounces Gruyère, shredded on the large holes of a box grater (about 1 1/2 cups)
  • 1/3 cup grated Parmesan
  • 8 large eggs
  • 2 1/2 cups evaporated milk, or half-and-half
  • 1 teaspoon fresh thyme leaves, roughly chopped

Lightly grease a 9-by-13-inch casserole dish with olive oil. Combine bread cubes, 2 tablespoons olive oil, 1/4 teaspoon salt and several grinds of black pepper in a large bowl, then toss to coat. Heat a large skillet over medium heat. Add bread to skillet and cook until golden brown, tossing occasionally, until bread becomes toasted, about 8 minutes. Return bread to bowl to cool. 

Wipe out skillet, then add remaining 2 tablespoons oil and heat over medium-high heat. Add mushrooms in one layer and cook, stirring as little as possible, until they start to brown. Stir and continue to brown, about 2 minutes more. Add garlic, thyme, 1/4 teaspoon salt and pepper; cook and stir 1 minute more. Fold in spinach and 1/4 teaspoon salt. Cook, stirring often until spinach is wilted, about 1 to 2 minutes more. Remove from heat. 

Add half of bread cubes to prepared dish, then sprinkle with half of the Gruyère and Parmesan. Cover evenly with mushroom-spinach mixture, then top with remaining bread cubes, Gruyère and Parmesan. Combine eggs, evaporated milk, 1/2 teaspoon of salt and several grinds of pepper in a large bowl and whisk together. Pour egg mixture evenly into casserole. Cover with plastic wrap and refrigerate overnight, or at least 6 hours.

Remove casserole from refrigerator 30 minutes before baking. Preheat oven to 350º F. Bake until golden brown and custard is set, about 50 to 55 minutes. Cool 15 minutes. Serve warm or at room temperature. 

– foodnetwork.com

Donna Ferguson

Donna Ferguson

I love to cook, garden, and write about all the things in Vancouver and the Northwest that make life so great.

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