Name: Spinach Florentine Breakfast Casserole Recipe
Prep time: 30 min
Cook time: 55 min
Total time: 2 h 25 min
Cuisine: American
Ingredients: 10 ounce frozen chopped spinach, thawed and drained; 1 tablespoon olive oil, plus more for greasing; 1 cup yellow onion, chopped; 3 cloves garlic, finely chopped; 8 ounce mascarpone cheese; 4 ounce Parmesan cheese, grated (divided); 2 teaspoons kosher salt (divided); 1 teaspoon black pepper (divided); 10 large eggs; 1.67 cups half-and-half; 0.25 teaspoon crushed red pepper; 6 English muffins, split into halves (bottom and top halves separated into 3 rows of 2 in a 13x9-inch dish)

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If you are looking for a delicious, comforting, and elegant start to your day, this Spinach Florentine Breakfast Casserole Recipe will quickly become one of your favorites. Imagine tender spinach mingling with rich mascarpone and Parmesan cheeses, all nestled between layers of English muffins and soaked in a luscious egg custard. It’s a creative twist on the classic spinach Florentine that’s perfect for morning gatherings or a leisurely weekend brunch. Best of all, it’s easy to assemble ahead of time, making your breakfast both impressive and stress-free.

Ingredients You'll Need

The image shows four steps of making a spinach dish. The first step is a white cloth-lined bowl with wet cooked spinach leaves, dark green in color, resting in it, placed on a wooden board over a white marbled surface. The second step shows a clear glass bowl with a creamy white and green mixture of spinach blended with cheese or sauce, with smooth, swirled texture, sitting on a wooden board over the white marbled surface. The third step is a white baking dish filled with a thick layer of the creamy spinach mix that looks evenly spread and baked, showing dark green leafy spots inside the pale white mixture. The final step shows the same baking dish topped with a layer of finely grated white cheese covering the creamy spinach mixture below, ready for baking or serving, all set on the white marbled texture. photo taken with an iphone --ar 4:5 --v 7

The magic of this dish lies in its simple but essential ingredients. Each component plays a vital role in creating the perfect balance of flavor, texture, and color in the casserole—from the creamy mascarpone and sharp Parmesan to the bright spinach and aromatic garlic.

10 ounce frozen chopped spinach: Thawed and drained thoroughly to avoid excess moisture in the casserole.

1 tablespoon olive oil: For sautéing onions and garlic to unlock their full flavor.
1 cup yellow onion, chopped: Adds natural sweetness and texture to the dish.
3 cloves garlic, finely chopped: Delivers a fragrant punch that complements the spinach beautifully.

8 ounce mascarpone cheese: Brings a rich, creamy smoothness that elevates the casserole’s flavor.
4 ounce Parmesan cheese, grated: Divided for layering and topping, it imparts a nutty, savory depth.
2 teaspoons kosher salt, divided: Enhances all the flavors without overpowering.

1 teaspoon black pepper, divided: Adds just the right touch of heat and earthiness.
10 large eggs: The custard base that holds everything together with a fluffy, tender texture.
1.67 cups half-and-half: Lightens the eggs and enriches the custard for a creamy consistency.

0.25 teaspoon crushed red pepper: For a subtle kick that keeps each bite exciting.
English muffins (bottom and top halves): The sturdy base for layering the spinach and custard, creating a delightful bite.

How to Make Spinach Florentine Breakfast Casserole Recipe

Step 1: Prepare the Spinach

First things first, carefully squeeze out as much liquid as you can from the thawed spinach using a clean kitchen towel; this step is key to preventing a soggy casserole. Then heat olive oil in a skillet and cook your chopped onions until translucent and sweet. Add the finely chopped garlic and cook just until fragrant—this quick sauté brings out a lovely aroma and flavor depth. Next, fold in the spinach and cook for a couple of minutes, allowing the mixture to dry out nicely. Set it aside to cool before moving to the next step.

Step 2: Mix the Cheesy Spinach Filling

Reserve a quarter cup of your cooked spinach mixture for later use and transfer the rest to a mixing bowl. Add creamy mascarpone cheese, half of the Parmesan, and half the salt and pepper to taste. Stir everything together until it forms a luscious, well-combined filling that will melt into the casserole layers.

Step 3: Whisk the Custard Base

In a separate large bowl, beat the eggs along with half-and-half, the reserved spinach mixture, the remaining Parmesan, salt, black pepper, and crushed red pepper flakes. This mixture will soak into the English muffins and meld with the cheesy spinach, creating a custardy, flavorful richness.

Step 4: Assemble the Casserole

Lightly grease a 13x9-inch baking dish to prevent sticking. Arrange the bottom halves of the English muffins in three rows of two, then spread the spinach mascarpone mixture evenly over them. Cover with the top muffin halves and pour the egg custard mixture on top, pressing down gently so the English muffins soak it all up. Sprinkle the remaining Parmesan cheese across the surface for a beautifully browned top.

Step 5: Chill and Bake

Cover the entire dish tightly with foil and refrigerate for a minimum of one hour, but feel free to leave it for up to 12 hours if prepping ahead. When you’re ready to bake, preheat your oven to 350°F and remove the foil. Bake the casserole until it’s just set and the top muffins turn golden and irresistible, about 55 minutes. Let it cool for ten minutes before serving to allow the flavors to settle and slicing to be easier.

How to Serve Spinach Florentine Breakfast Casserole Recipe

The image shows a baked dish in a white ceramic rectangular baking dish with a greenish tint from light reflection, containing four square portions. Each portion has three visible layers: a creamy white melted cheese base, a middle layer of dark green spinach mixed with cheese, and a top layer covered with a golden-brown melted cheese crust sprinkled with grated cheese, giving a slightly crispy texture. One square is being scooped out with a silver spoon, revealing melted white cheese and spinach inside. The background is a white marbled surface with a soft cloth underneath the dish. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

A sprinkle of fresh chopped parsley or a few basil leaves adds a fresh, vibrant contrast to the creamy casserole. You can also sprinkle a bit more grated Parmesan or some cracked black pepper right before serving for an extra burst of flavor that catches the eye.

Side Dishes

This casserole pairs beautifully with a crisp spinach and fruit salad to echo the spinach flavors while adding lightness and sweetness. Fresh fruit like sliced oranges, strawberries, or melon will provide perfect balance to such a rich and hearty dish.

Creative Ways to Present

Consider serving this casserole in individual ramekins for a charming, personal touch at brunch — it’s a great way to impress guests. Alternatively, garnish each slice with a dollop of crème fraîche or sour cream for added creaminess and a bit of tang that brightens each bite.

Make Ahead and Storage

Storing Leftovers

Store any leftover casserole in an airtight container in the refrigerator for up to three days. The flavors deepen overnight, so leftovers are actually a delightful next-day treat. Just be sure to cover it well to keep moisture locked in.

Freezing

This casserole freezes well either before baking or after it has been cooked and cooled. Wrap it tightly in foil and place it in a freezer-safe container; it should keep well for up to two months. Thaw in the refrigerator overnight before reheating for best results.

Reheating

To reheat, place individual slices or the whole casserole in a 350°F oven until warmed through, about 15-20 minutes for individual portions, or 30-40 minutes for a whole dish. Avoid using the microwave to keep the texture just right when reheated.

FAQs

Can I use fresh spinach instead of frozen?

Yes, you can substitute fresh spinach, but you’ll need about twice the volume since fresh spinach cooks down significantly. Make sure to sauté and drain the cooked spinach thoroughly to avoid excess moisture in the casserole.

Is mascarpone cheese essential for this recipe?

Mascarpone adds a unique creaminess and subtle sweetness that enriches the casserole, but it can be substituted with cream cheese or ricotta if needed. Just keep in mind that this may alter the final texture slightly.

Can I make this vegetarian-friendly?

This recipe is already vegetarian since it contains no meat. Just ensure your Parmesan cheese is vegetarian-friendly, as some cheeses use animal rennet.

How far in advance can I prepare this casserole?

You can assemble and refrigerate the casserole for up to 12 hours before baking, making it perfect for preparing the night before a big brunch or special occasion.

What can I do to make this recipe spicier?

If you want more heat, increase the crushed red pepper flakes or add a dash of hot sauce to the egg custard. Freshly ground black pepper also adds a nice bite without overwhelming the spinach flavors.

Final Thoughts

There’s something so comforting and special about waking up to a warm, cheesy, spinach-filled casserole that feels both elegant and homey. This Spinach Florentine Breakfast Casserole Recipe is the kind of dish that brings people together around the breakfast table, whether for a casual weekend or a festive brunch. Don’t hesitate to give it a try—you’ll be delighted to find yourself making it again and again!

Ingredients You'll Need