A Hearty, Flavorful, and Make-Ahead Morning Meal
This casserole is savory, cheesy, and packed with vegetables, making it a perfect breakfast or brunch dish for families, weekend gatherings, or meal prep. The combination of fresh spinach, crumbly feta cheese, and fluffy eggs creates a rich, satisfying texture, while optional additions like bell peppers, onions, or herbs add depth and color.
Baking it in the oven ensures even cooking, and the result is a golden, lightly browned top with a creamy, flavorful center. You can prepare it ahead of time and reheat slices for an easy weekday breakfast.
Ingredients (Serves 6–8)
Vegetables
- 10 oz (280 g) fresh spinach, washed, trimmed, and roughly chopped (or 1 package frozen spinach, thawed and drained)
- 1 medium onion, finely chopped
- 1 red bell pepper, diced
- 2 cloves garlic, minced
Eggs and Dairy
- 8 large eggs
- 1 cup milk (whole or 2% for best texture)
- 1 teaspoon Dijon mustard (optional, adds depth)
- ¼ teaspoon black pepper
- ½ teaspoon salt (adjust if using salty feta)
- ¼ teaspoon crushed red pepper flakes (optional, for slight heat)
Cheese
- 1 cup crumbled feta cheese (approx. 150 g)
- ½ cup shredded mozzarella or cheddar (optional, for extra melty texture)
Optional Add-Ins
- ½ teaspoon dried oregano or thyme
- 2 tablespoons fresh parsley, chopped, for garnish
- ½ cup cooked breakfast sausage, crumbled, or diced ham (optional protein boost)
For the Baking Dish
- 1 tablespoon olive oil or nonstick spray to grease the dish
Step 1: Prepare the Vegetables
- Preheat the oven to 180°C (350°F).
- Heat 1 tablespoon olive oil in a skillet over medium heat.
- Add the chopped onion and bell pepper. Sauté for 4–5 minutes until soft and fragrant.
- Add minced garlic and sauté for 30 seconds until aromatic.
- Add the fresh spinach a handful at a time, stirring until wilted (or cook frozen spinach until fully drained of excess water).
- Remove from heat and let the mixture cool slightly.
Tip: Excess moisture can make the casserole watery. Squeeze cooked spinach in a clean kitchen towel to remove extra water.
Step 2: Mix the Egg Base
In a large mixing bowl:
- Crack in all 8 eggs.
- Add the milk, Dijon mustard, salt, black pepper, and optional red pepper flakes.
- Whisk thoroughly until the mixture is smooth and slightly frothy.
Tip: Whisking the eggs well introduces air, giving the casserole a lighter, fluffier texture.
Step 3: Combine Ingredients
- Fold the cooled spinach and vegetable mixture into the egg mixture.
- Add the crumbled feta and optional shredded mozzarella or cheddar.
- If using cooked meat or herbs, fold them in gently.
The final mixture should be evenly combined but not overmixed, so the cheese remains distributed and pockets of feta melt beautifully during baking.
Step 4: Prepare the Baking Dish
- Lightly grease an 8×8 inch (or 9×9 inch) oven-safe baking dish with olive oil or nonstick spray.
- Pour the mixture into the dish, spreading it evenly.
- Optional: Sprinkle a little extra feta or shredded cheese on top for a golden crust.
Step 5: Bake the Casserole
- Place the dish in the preheated oven.
- Bake for 35–40 minutes, or until the top is lightly golden and the center is set.
- Test doneness by inserting a toothpick into the center; it should come out clean.
- Slight jiggle is fine, as the casserole will continue to set after resting.
- Remove from the oven and let it cool for 5–10 minutes before slicing.
Tip: Allowing it to rest helps the casserole firm up, making it easier to serve neat slices.
Serving Suggestions
- Serve warm with a side of fresh fruit or roasted potatoes for a complete breakfast.
- Garnish with chopped fresh parsley or chives for color and brightness.
- Leftovers can be refrigerated for 3–4 days and reheated in the oven or microwave.
Variations and Substitutions
- Vegetarian: Keep it simple with spinach, onion, and bell peppers.
- Meaty: Add cooked bacon, sausage, or diced ham for extra protein.
- Low-Carb/Keto-Friendly: No bread or flour needed; the eggs and cheese make it naturally low-carb.
- Cheese Swap: Use goat cheese, ricotta, or sharp cheddar instead of feta for a different flavor profile.
- Extra Veggies: Mushrooms, zucchini, or kale can easily be added for more nutrients.
Tips for Perfect Texture
- Avoid overcooking: Overbaking can make eggs rubbery. Start checking at 30 minutes.
- Drain vegetables well: Moisture from spinach or bell peppers can make the casserole watery.
- Use room-temperature eggs: This helps the eggs cook evenly and results in a smoother texture.
Why This Casserole Works
- The eggs provide structure and protein.
- The spinach adds moisture, fiber, and nutrients.
- The feta contributes creaminess and saltiness, complementing the greens.
- Baking allows flavors to develop fully while keeping a fluffy, custard-like interior.
It’s simple enough for a weekday morning but impressive enough for brunch with family or friends.
