Spinach Mushroom Breakfast Casserole

Spinach mushroom breakfast casserole with cheddar, sautéed onions, and bread cubes. This easy vegetarian egg bake is ready from oven to table in about an hour.

Prep: 15 min · Cook: 45 min · Yield: 6 · Method: Oven

Ingredients

• 8 eggs
• 2 cups fresh spinach
• 8 ounces mushrooms
• 1 cup milk
• 1 cup cheddar cheese
• 4 cups bread cubes
• 0.5 medium onion
• 1 tablespoon olive oil
• 1 teaspoon kosher salt
• 0.5 teaspoon black pepper

Cooking instructions

1. Heat the oven to 350°F. Lightly grease a 9-by-13-inch baking dish. (about 5 min) — 350°F
2. Heat the olive oil in a large skillet over medium heat. Add the onion and mushrooms, season with half the salt and pepper, and sauté until the mushrooms release their moisture and the onion softens, about 7 minutes. Add the spinach and cook until wilted, about 2 minutes. (about 9 min) — Medium heat
3. Arrange the bread cubes in the baking dish. Layer the mushroom mixture evenly over the bread. (about 3 min)
4. Whisk the eggs, milk, and remaining salt and pepper until smooth. Pour evenly over the bread and vegetables, pressing gently so the bread absorbs the egg mixture. (about 3 min)
5. Top evenly with the cheddar. Bake until the center is set, the edges are puffed, and the casserole reaches 160°F, about 30 to 35 minutes. (about 33 min) — 350°F
6. Rest the casserole for 10 minutes, then cut into portions and serve warm. (about 10 min)