Cheesy Spinach-Potato Egg Casserole recipe

There are certain dishes that just feel like a warm hug on a plate, and for my family, this Cheesy Spinach-Potato Egg Casserole is the epitome of comfort. For years, I searched for the perfect all-in-one breakfast bake—something heartier than a frittata, less fussy than individual omelets, and substantial enough to quell the “I’m still hungry” chorus from my kids after a standard breakfast. This casserole was a game-changer. The first time I pulled its golden-brown, bubbly top from the oven, the aroma of roasted potatoes, savory garlic, and sharp cheddar filled the entire house. It wasn’t just breakfast; it felt like an event. The best part? It was a smash hit. The tender potatoes provide a satisfying heartiness, the spinach adds a touch of welcome green, and the cheesy egg custard ties it all together in the most delicious way. It has since become our Sunday morning ritual and my secret weapon for stress-free holiday brunches. It’s the kind of dish that gets scraped clean every single time.

Complete with the ingredients amount

This recipe is designed to be a crowd-pleasing, hearty breakfast or brunch centerpiece. It relies on simple, wholesome ingredients to create a dish that is both satisfying and packed with flavor. It serves 8-10 people generously.

• 1 ½ lbs Yukon Gold or Red Potatoes (about 4-5 medium potatoes): These waxy potatoes hold their shape well and have a creamy texture when cooked, making them ideal for a casserole.
• 1 tbsp Olive Oil: For roasting the potatoes.
• 1 medium Yellow Onion, finely chopped: Forms a sweet, savory base for the casserole.
• 2 cloves Garlic, minced: Adds a crucial layer of aromatic depth.
• 1 (10 oz) package Frozen Chopped Spinach, thawed and squeezed bone dry: Frozen spinach is a fantastic, convenient shortcut. The key is to remove all excess water.
• 12 large Eggs: The star of the custard base.
• 1 cup Milk (whole or 2% recommended): Creates a tender, creamy custard. You can also use half-and-half for an even richer result.
• 1 tsp Salt: Essential for seasoning the eggs and potatoes.
• ½ tsp Black Pepper, freshly ground: For a touch of warmth and spice.
• ½ tsp Smoked Paprika (optional, but recommended): Lends a subtle smoky flavor that complements the cheese and potatoes beautifully.
• 2 ½ cups Shredded Cheese, divided: A good melting cheese is key.
  • Sharp Cheddar Cheese is a fantastic choice for its bold flavor.
  • Monterey Jack or Gruyère are also excellent options. Gruyère adds a nutty sophistication.

Instructions

The secret to a perfect, non-watery egg casserole lies in preparing the components properly before baking. Following these detailed steps will guarantee a flawless result.

Part 1: Preparing the Potato and Veggie Base

1. Roast the Potatoes: Preheat your oven to 400°F (200°C). Wash and dice the potatoes into uniform ½-inch cubes (peeling is optional). On a large baking sheet, toss the diced potatoes with 1 tablespoon of olive oil, ½ teaspoon of salt, and ¼ teaspoon of black pepper. Spread them into a single, even layer. Roast for 20-25 minutes, flipping halfway through, until the potatoes are tender and lightly golden brown at the edges. Pre-cooking the potatoes ensures they are perfectly cooked through in the final casserole.
2. Prepare the Baking Dish: While the potatoes are roasting, generously grease a 9×13 inch glass or ceramic baking dish. Reduce the oven temperature to 375°F (190°C) for the final bake.
3. Squeeze the Spinach (The Most Important Step!): Place the thawed spinach in the center of a clean kitchen towel, cheesecloth, or several layers of heavy-duty paper towels. Gather the ends and twist, squeezing as hard as you can to remove every last drop of water. You should be left with a dense, compact ball of spinach. This step is absolutely critical to prevent a soggy casserole.
4. Sauté the Aromatics: In a medium skillet over medium heat, add the chopped yellow onion. Cook for 5-7 minutes until softened and translucent. Add the minced garlic and cook for another minute until fragrant. Remove from heat.
5. Layer the Casserole: Spread the roasted potatoes evenly across the bottom of the prepared baking dish. Crumble the dry spinach over the potatoes, followed by the cooked onion and garlic mixture. Sprinkle 1 ½ cups of the shredded cheese evenly over the top of the vegetables.

Part 2: Assembling and Baking the Casserole

1. Make the Egg Custard: In a large bowl, crack all 12 eggs. Add the cup of milk, the remaining ½ teaspoon of salt, ¼ teaspoon of black pepper, and the optional smoked paprika. Whisk vigorously for about a minute, until the eggs are completely broken down, the mixture is uniform in color, and slightly frothy. A thorough whisking incorporates air and leads to a fluffier casserole.
2. Pour and Combine: Gently pour the whisked egg mixture evenly over the layers of potatoes, spinach, and cheese in the baking dish.
3. Top with Cheese: Sprinkle the remaining 1 cup of shredded cheese over the top of the casserole.
4. Bake to Golden Perfection: Place the baking dish in the preheated 375°F (190°C) oven. Bake for 35-45 minutes. The casserole is done when the center is set (doesn’t jiggle when gently shaken) and a knife inserted into the middle comes out clean. The top should be puffed up and beautifully golden brown.
5. Let It Rest: This step is crucial. Remove the casserole from the oven and let it rest on a wire rack for at least 10-15 minutes before slicing and serving. This allows the casserole to set up firmly, making it much easier to cut into clean, neat squares.

Nutrition Facts (Servings and calories per serving)

The nutritional information is an estimate and can vary based on the specific type of cheese and milk used.

• Servings: 10 generous servings
• Serving Size: One 3×3 inch square (approx.)
• Calories Per Serving: Approximately 280-340 calories.

Preparation time

This recipe is perfect for a weekend morning or for meal-prepping, with much of the time being hands-off baking.

• Active Preparation Time: 20-25 minutes (for chopping and sautéing)
• Baking Time: 35-45 minutes (plus 20-25 minutes for roasting potatoes)
• Total Time: Approximately 1 hour 15 minutes – 1 hour 30 minutes

How to Serve

This versatile casserole is a meal in itself but can be dressed up in numerous ways to suit any occasion.

• As a Simple, Hearty Breakfast:
  • Serve a warm square on its own. It’s a perfectly balanced, low-carb meal packed with protein and vegetables.
• With Fresh and Flavorful Toppings:
  • Offer a “toppings bar” to let everyone customize their slice. Great options include:
    • Salsa or Pico de Gallo: Adds a fresh, zesty kick.
    • Sliced Avocado or Guacamole: For a creamy, healthy fat.
    • A dollop of Sour Cream or Plain Greek Yogurt: For a cool, tangy contrast.
    • Your favorite Hot Sauce: For those who like a little heat.
    • Freshly chopped Chives or Cilantro: For a pop of fresh, herbaceous flavor.
• As the Centerpiece of a Brunch Spread:
  • This casserole is the perfect anchor for a full brunch menu. Serve it alongside:
    • Crispy bacon or breakfast sausage links.
    • A vibrant fresh fruit salad.
    • Buttery biscuits, croissants, or a basket of assorted pastries.
• For “Breakfast-for-Dinner”:
  • Pair a hearty slice with a simple side salad tossed in a light vinaigrette. This creates a satisfying, easy, and well-rounded weeknight meal.

Additional tips (5 tips)

These five expert tips will help you master this casserole and adapt it to your liking.

1. Master the Potato: The foundation of this casserole is the potato layer. Roasting them first, as directed, is the best method as it develops a deep flavor and ensures they are perfectly tender. For a shortcut, you can use about 4-5 cups of frozen diced potatoes or Southern-style hash browns (no need to thaw, just toss with oil and seasonings and roast as directed). You can even use frozen tater tots for a fun, kid-friendly twist—just arrange them on the bottom of the dish and bake for 15 minutes before adding the other layers.
2. The Squeeze is Non-Negotiable: We can’t say it enough: you must squeeze every possible drop of water from the thawed spinach. If you skip or skimp on this step, the excess water will release into the eggs as they bake, preventing the custard from setting properly and resulting in a watery, weeping, and structurally unsound casserole. A clean dish towel or cheesecloth is your best tool for this job.
3. Cheese is a Key Flavor Component: Don’t be afraid to experiment with your cheese choices. A sharp cheddar provides a classic, bold flavor. For a nuttier, more sophisticated casserole, use Gruyère. For an extra-gooey, melty casserole, use Monterey Jack. For the best flavor and melting quality, always buy a block of cheese and shred it yourself. Pre-shredded cheeses contain anti-caking agents that can inhibit a perfectly smooth melt.
4. The Ultimate Make-Ahead Breakfast: This casserole is a meal-prepper’s dream.
   • Assemble Ahead Method: You can fully assemble the casserole (without baking) the night before. Cover it tightly with plastic wrap and store it in the refrigerator. In the morning, remove the plastic wrap and bake as directed, adding 5-10 minutes to the baking time since it’s starting from cold.
   • Bake Ahead Method: Bake the entire casserole as directed. Let it cool completely, then cover and store in the refrigerator for up to 4 days. Reheat individual slices in the microwave or place the entire dish back in a 350°F oven until warmed through.
5. Customize Your Casserole: Think of this recipe as a delicious template. It’s a perfect “clean out the fridge” dish. You can swap or add other vegetables like sautéed bell peppers, mushrooms, or steamed broccoli florets. You can also add about 1 cup of cooked, crumbled meat like breakfast sausage, bacon, or diced ham for an even heartier meal. Just make sure any additions are pre-cooked and drained of fat before layering them in.

FAQ section ( 5 Q/A)

Here are answers to some of the most frequently asked questions about this recipe.

1. Why did my egg casserole turn out watery or spongy?
A watery or spongy casserole is almost always caused by excess moisture or over-baking. The most likely culprit for wateriness is not squeezing the spinach dry enough or using raw vegetables that release water during baking. A spongy, rubbery texture is a sign that the casserole was over-baked. Eggs, when cooked for too long or at too high a temperature, will tighten up and squeeze out liquid. Bake only until the center is just set, and remember that it will continue to cook a bit as it rests.

2. Can I use fresh spinach instead of frozen?
Yes, you can absolutely use fresh spinach. You will need about 1-1.5 pounds of fresh spinach to equal a 10 oz package of frozen. To prepare it, sauté the fresh spinach in a large skillet until it is completely wilted down. Transfer the wilted spinach to a colander and press down firmly with a spoon to squeeze out as much liquid as possible before chopping and adding it to the casserole.

3. How do I store and freeze this egg casserole?
To Store: Let the casserole cool completely. Cover the dish tightly or transfer individual slices to an airtight container. Store in the refrigerator for up to 4 days.
To Freeze: This casserole freezes beautifully. Let it cool completely, then cut it into individual portions. Wrap each portion tightly in plastic wrap and then in aluminum foil, or place them in a freezer-safe bag. It can be frozen for up to 3 months. To reheat, you can thaw overnight in the fridge or microwave directly from frozen.

4. Can I make this recipe dairy-free?
Yes, it’s easy to adapt this recipe to be dairy-free. Use your favorite unsweetened, unflavored plant-based milk (like almond or soy milk) in place of the cow’s milk. For the cheese, you can use a brand of dairy-free shredded cheese that you enjoy. For a cheesy flavor without using dairy substitutes, you can add about ¼ cup of nutritional yeast to the egg mixture.

5. Can I make this in a different sized pan or in muffin tins?
Yes, but you will need to adjust the baking time.

• For an 8×8 or 9×9 inch square pan: The casserole will be thicker, so you will likely need to increase the baking time by 10-15 minutes.
• For Muffin Tins: To make individual grab-and-go portions, grease a muffin tin well and divide the mixture evenly among the cups. Bake at 375°F for 20-25 minutes, or until the centers are set. This is a fantastic option for portion control and easy breakfasts.

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